Major interaction on record — check this product against your medications before combining. Based on 14 of 16 ingredients. Check your meds →
Dietary supplement

Alphagen Strawberry Lemonade Ingredients & Drug Interactions

by Morphogen Nutrition

Alphagen Strawberry Lemonade label
See full label image
Powder Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Alphagen Strawberry Lemonade against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

Alphagen Strawberry Lemonade is a dietary supplement by Morphogen Nutrition with 16 active ingredients. Its ingredients are commonly taken for improving high-intensity exercise performance, building muscle strength and size, sports and athletic training.Based on those ingredients, 1,540 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Bioperine Nature's Thermonutrient, Synephrine HCl, Theobromine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Alphagen Strawberry Lemonade by Morphogen Nutrition

Ask about any prescription or over-the-counter medication and we check it for interactions with Alphagen Strawberry Lemonade by Morphogen Nutrition — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.

HelloPharmacist Scorecard of Alphagen Strawberry Lemonade by Morphogen Nutrition

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 12, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 16 of its 16 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Alphagen Strawberry Lemonade contains 16 ingredients, of which the active ones are Creatine Monohydrate (for muscle strength and athletic performance), L-Tyrosine (an amino acid), Beta-Alanine (for athletic performance), L-Theanine (for cognition and relaxation), Caffeine Anhydrous (for mental alertness), Huperzine A (for cognitive function), Synephrine HCl and Hordenine HCl (stimulants), DMAE Bitartrate, Macuna pruriens (which contains L-dopa), Alpha-GPC (for brain health), Theacrine (a caffeine-like stimulant), Theobromine (caffeine-related compound from cocoa), and Black Pepper extract (Bioperine, for absorption). The inactive ingredients are natural and artificial flavoring, sweeteners (Sucralose and Acesulfame Potassium), citric acid, silica (Sipernat), and food coloring.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: high energy pre-workout performance and focus.
  • We looked for evidence on: Athletic performance, Attention deficit-hyperactivity disorder (ADHD), Cognitive function, Exercise-induced muscle damage, Exercise-induced muscle soreness, Fatigue — and 4 related terms.
  • The strongest evidence on file: Caffeine is rated "Likely Effective" for Athletic performance (Natural Medicines).
  • Also on file: Caffeine is rated "Likely Effective" for Mental alertness.
  • Also on file: Creatine is rated "Possibly Effective" for Athletic performance.

Creatine is possibly effective for muscle strength, athletic performance, and certain rare neurological conditions, though it's possibly ineffective for bone density and Huntington disease. L-Tyrosine is effective for a rare amino acid disorder (PKU) and possibly effective for mental function and memory, but possibly ineffective for athletic performance.

Beta-Alanine is possibly effective for athletic and physical performance. L-Theanine is possibly effective for cognitive function.

Caffeine is likely effective for mental alertness and athletic performance. Huperzine A is possibly effective for Alzheimer disease.

For most other ingredients in this product — Synephrine, Hordenine, DMAE, Macuna pruriens, Theacrine, and Black Pepper — the evidence for their stated uses is not established or is insufficient to rate. Alpha-GPC is possibly effective for Alzheimer disease, and Theobromine is possibly effective for cardiovascular health.

The evidence, ingredient by ingredient Creatine Tyrosine Beta-alanine Theanine Caffeine Huperzine A Bitter Orange Hordenine

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 13 of the 14 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 12 of 14.
  • General safety write-ups exist for 14 of 14.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Creatine is generally well tolerated but should be avoided in pregnancy, avoided while breastfeeding, and used cautiously if you have kidney issues — common mild side effects include dehydration, diarrhea, muscle cramps, and water retention. L-Tyrosine is generally well tolerated with the most common side effects being fatigue, headache, heartburn, and nausea; avoid it in pregnancy and use cautiously while breastfeeding.

Beta-Alanine causes a harmless tingling sensation on the skin in most people and should be avoided in pregnancy and while breastfeeding. L-Theanine is generally well tolerated short-term but long-term safety is not well studied; avoid in pregnancy and while breastfeeding.

Caffeine is generally safe in moderate amounts but at high doses can cause anxiety, insomnia, tremors, and nausea — limit intake in pregnancy and moderate intake while breastfeeding. Huperzine A can cause dose-dependent cholinergic side effects (blurred vision, constipation, nausea, vomiting, diarrhea) and should be avoided in pregnancy and while breastfeeding.

Synephrine HCl can raise blood pressure and heart rate and should be avoided in pregnancy and while breastfeeding. Hordenine has very limited human safety data, is structurally similar to stimulants, and should be avoided in pregnancy and while breastfeeding.

DMAE may cause digestive upset, drowsiness, or mood changes and should be avoided in pregnancy; safety while breastfeeding is unknown. Macuna pruriens contains L-dopa, can affect dopamine, should be avoided in pregnancy, and avoided while breastfeeding because it can lower milk supply.

Alpha-GPC is generally well tolerated in studies; avoid unless your doctor directs otherwise in pregnancy and while breastfeeding. Theacrine, Theobromine, and Black Pepper should all be avoided in pregnancy and while breastfeeding due to insufficient safety data.

Side effects, ingredient by ingredient Creatine Tyrosine Beta-alanine Theanine Caffeine Huperzine A Bitter Orange Hordenine

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 12 of the 14 matched ingredients can interact with medications — Deanol, Huperzine A, Black Pepper, Cocoa, Bitter Orange, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications; lithium; Parkinson's medications.
  • For scale: 1,541 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check if you use Ephedrine (Major), MAOIs or Midazolam (Major from Synephrine and Macuna), Methyldopa or L-dopa (Major from Macuna), blood pressure drugs, antidiabetes medications, heart drugs (especially those affecting heart rhythm), brain medications (anticholinergic or cholinergic), cough suppressants, certain antibiotics, or barbiturates. If any apply, review them with your pharmacist using the search tool on this page.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

This is a multi-ingredient sports and cognition supplement with potent stimulants and active compounds. It may appeal to athletes wanting creatine and beta-alanine, or people seeking mental-focus support.

However, if you take any blood pressure medication, MAOI antidepressant, Parkinson medication (L-dopa), sedatives, heart rhythm drugs, diabetes drugs, or other prescriptions, you must check your exact medications with our tool first — the interaction risk is real and serious. Talk to your pharmacist before you start.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 14 of 16 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 25, 2020.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Alphagen Strawberry Lemonade, straight from the product label.

Brand Morphogen Nutrition
Barcode (UPC) 653341224545
Net contents 17.71 oz; 496 Gram(s)
Market status On market
Date entered into DSLD Jan 25, 2020
DSLD ID 212746
Product type Other Combinations
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Alphagen Strawberry Lemonade by Morphogen Nutrition, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
12.4 Gram(s)
Maximum serving Sizes:
24.8 Gram(s)
Servings per container
20
UPC/BARCODE
653341224545
IngredientAmount% DV
Creatine Monohydrate5000 mg--
L-Tyrosine2000 mg--
Beta-Alanine3200 mg--
L-Theanine400 mg--
Caffeine Anhydrous200 mg--
Huperzine A200 mcg--
Synephrine HCl50 mg--
Hordenine HCl50 mg--
Dimethylaminoethanol (DMAE) Bitartrate750 mg--
Macuna pruriens750 mg--
Alpha-Glyceryl Phosphoryl Choline600 mg--
Theacrine250 mg--
Methylliberine250 mg--
Theobromine200 mg--
Bioperine Nature's Thermonutrient10 mg--
Citrulline Malate8000 mg--

Other ingredients: Natural & Artificial flavor, Sipernat, Sucralose, Acesulfame Potassium, Citric Acid, FD&C #40

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

Recommended Use: As a dietary supplement, mix 1 rounded scoop (24.8g) in 12-16oz water (depending on flavor preference) and consume 15-20 minutes pre-workout. Start with 1/2 scoop to assess tolerance. Gradually build up to 1 rounded scoop. Do not use more than one scoop at a time. Do not use more than 3 (three) scoops in a 24 hour period.

Brand IP Statement(s)

AlphaSize is a registered trademark of Chemi Nutra TeaCrine is a registered trademark and protected by patents pending serial no. 61/903,362; under exclusive global distribution by Compound Solutions, Inc. Dynamine is a trademark and protected by patents pending serial no. 61/903,362; under exclusive global distribution by Compound Solutions, Inc. BioPerine is protected under one or more of the following U.S. patents: #5,536,506; #5,744,161; #5,861,415; #5,972,382 and #6,054,585. BioPerine and Nature's Thermonutrient are registered trademarks of Sabinsa Corp

Precautions

Warnings: Not intended for use by persons under the age of 18.

If you are pregnant or nursing or are taking any prescription medications, consult your health care professional before using this or any other dietary supplement product.

Immediately discontinue use and consult your doctor if any adverse reactions occur.

Keep out of reach of children.

Storage

Store in a cool, dry place and avoid excessive heat.

Formulation

High energy pre-workout Performance Focus Euphoria

High potency formula

Maximum performance

Multi-phase strength and endurance enhancement Exercise intensity and alertness Cognition, memory and, mental focus Blood flow, nutrient delivery and muscle cell volume Decreases acid and ammonia build-up & prevents fatigue Lipolysis and fatty acid oxidation Promoting feelings of well-being and euphoria

FDA Statement of Identity

Dietary Supplement

General Statements

Specializes in developing no BS, scientifically validated, effectively dosed and affordable sports nutrition supplements Knowledge Honesty Integrity No BS

Join the takeover

Formula

Pure ingredients

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Seals/Symbols

Manufactured in THE USA for Morphogen Nutrition GMP Good Manufacturing Practice Quality Product FDA registered Lab Tested 3rd party certified for purity & potency

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Alphagen Strawberry Lemonade by Morphogen Nutrition label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Alphagen Strawberry Lemonade label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Alphagen Strawberry Lemonade by Morphogen Nutrition

These are the 16 active ingredients this product is made of. Select any to open its full monograph.

Serving size12.4 Gram(s) Dosage formPowder Servings per container20 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Creatine Monohydrate

No known
interactions
5000 mg per serving

Creatine is one of the most studied sports supplements, with solid evidence that it can boost strength and performance during short, high-intensity ac...

Creatine Monohydrate monograph & interactions

L-Tyrosine

Interacts with
21 drugs
2000 mg per serving

L-tyrosine is an amino acid your body uses to make brain chemicals like dopamine and norepinephrine. Some studies suggest it may help mental performan...

L-Tyrosine monograph & interactions

Beta-Alanine

No known
interactions
3200 mg per serving

Beta-alanine is an amino acid taken mostly by athletes to raise muscle carnosine, which may help buffer acid and reduce fatigue during short, high-int...

Beta-Alanine monograph & interactions

L-Theanine

Interacts with
565 drugs
400 mg per serving

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong dro...

L-Theanine monograph & interactions

Caffeine Anhydrous

Interacts with
655 drugs
200 mg per serving

Caffeine is a natural stimulant found in coffee, tea, and many other plants and products. In moderate amounts it can boost alertness and reduce tiredn...

Caffeine Anhydrous monograph & interactions

Huperzine A

Interacts with
219 drugs
200 mcg per serving

Huperzine A is a purified compound from a Chinese clubmoss that acts like a mild cholinesterase inhibitor, similar in mechanism to some prescription A...

Huperzine A monograph & interactions

Synephrine HCl

Interacts with
957 drugs
50 mg per serving

Bitter orange is a citrus fruit whose extracts contain synephrine, a mild stimulant often added to weight-loss and energy supplements. Evidence that i...

Synephrine HCl monograph & interactions

Hordenine HCl

Interacts with
329 drugs
50 mg per serving

Hordenine is a natural alkaloid found in barley and some cacti that is marketed as a stimulant for energy, focus, and fat loss, but solid human eviden...

Hordenine HCl monograph & interactions

Dimethylaminoethanol (DMAE) Bitartrate

Interacts with
219 drugs
750 mg per serving

Deanol (DMAE) is a compound related to choline that is marketed for memory, focus, and mood, but solid human evidence for most of these uses is limite...

Dimethylaminoethanol (DMAE) Bitartrate monograph & interactions

Macuna pruriens

Interacts with
193 drugs
750 mg per serving Form: L-DOPA

Cowhage (Mucuna pruriens) is a tropical legume best known as a natural source of L-dopa, the compound the body turns into dopamine. It is most studied...

Macuna pruriens monograph & interactions

Alpha-Glyceryl Phosphoryl Choline

Interacts with
16 drugs
600 mg per serving Form: Alpha-GPC

Alpha-GPC is a choline-containing compound used mainly for memory, brain health, and as a choline source. There is some evidence it may help cognition...

Alpha-Glyceryl Phosphoryl Choline monograph & interactions

Theacrine

Interacts with
248 drugs
250 mg per serving Form: TeaCrine

Theacrine is a caffeine-like compound found naturally in certain tea plants and is sold in supplements for energy, focus, and mood. Early human studie...

Theacrine monograph & interactions

Methylliberine

250 mg per serving Form: Dynamine

Theobromine

Interacts with
661 drugs
200 mg per serving

Cocoa is rich in plant compounds called flavanols that may modestly support blood vessel function and blood pressure, but most chocolate products are...

Theobromine monograph & interactions

Bioperine Nature's Thermonutrient

Interacts with
1,019 drugs
10 mg per serving

Black pepper is a common kitchen spice that is generally safe in the amounts used in food. Its extract, piperine, is mostly added to supplements to he...

Bioperine Nature's Thermonutrient monograph & interactions

Citrulline Malate

8000 mg per serving

Other (inactive) ingredients: Natural & Artificial flavor, Sipernat, Sucralose, Acesulfame Potassium, Citric Acid, FD&C #40. These complete the product’s ingredient list but are not active constituents.

Interaction report

Alphagen Strawberry Lemonade by Morphogen Nutrition Drug Interactions

Want to check YOUR meds against Alphagen Strawberry Lemonade?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
1,540Drugs
26 Major 1,475 Moderate 39 Minor

Ingredients driving the most interactions

Bioperine Nature's Thermonutrient 1,019
Synephrine HCl 957
Theobromine 661
Caffeine Anhydrous 655
L-Theanine 565

Individual Drug Interactions

The ingredients in Alphagen Strawberry Lemonade interact with 1,540 drugs. Click any drug to see the details.

12 of the 16 ingredients in Alphagen Strawberry Lemonade interact with drugs. Each result below shows which ingredient is responsible. Bioperine Nature's Thermonutrient Synephrine HCl Theobromine Caffeine Anhydrous L-Theanine Hordenine HCl Theacrine Huperzine A Dimethylaminoethanol (DMAE) Bitartrate Macuna pruriens L-Tyrosine Alpha-Glyceryl Phosphoryl Choline

Each ingredient & the kinds of drugs it affects

For each ingredient in Alphagen Strawberry Lemonade with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Bioperine Nature's Thermonutrient17 drug types · 1,019 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, black pepper might increase the risk of bleeding when taken with antiplatelet or anticoagulant drugs.
In vitro research shows that piperine, a constituent of black pepper, seems to inhibit platelet aggregation. This has not been reported in humans.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, black pepper might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research shows that piperine, a constituent of black pepper, can reduce blood glucose levels. Monitor blood glucose levels closely. Dose adjustments might be necessary.

Likelihood Possible Evidence D
Atorvastatin (Lipitor)

Theoretically, black pepper might increase blood levels of atorvastatin.
Animal research shows that taking piperine, a constituent of black pepper, 35 mg/kg can increase the maximum serum concentration of atorvastatin three-fold. This has not been reported in humans.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, black pepper might increase the effects and side effects of cyclosporine.
In vitro research shows that piperine, a constituent of black pepper, increases the bioavailability of cyclosporine. This has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, black pepper might increase levels of drugs metabolized by CYP2D6.
In vitro research suggests that some constituents of black pepper inhibit CYP2D6. This has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, black pepper might increase levels of drugs metabolized by CYP3A4.
In vitro research and pharmacokinetic simulation data suggest that piperine, a constituent of black pepper, as well as the pepper fruit seem to inhibit CYP3A4. This has not been reported in humans.

Likelihood Possible Evidence D
Lithium

Theoretically, black pepper might increase blood levels of lithium due to its diuretic effects. The dose of lithium might need to be reduced.
Black pepper is thought to have diuretic properties.

Likelihood Probable Evidence D
Nevirapine (Viramune)

Black pepper might increase blood levels of nevirapine.
Clinical research shows that piperine, a constituent of black pepper, increases the plasma concentration of nevirapine. However, no adverse effects were observed in this study.

Likelihood Probable Evidence D
P-Glycoprotein Substrates

Theoretically, black pepper might increase levels of P-glycoprotein substrates.
In vitro research shows that piperine, a constituent of black pepper, seems to inhibit P-glycoprotein.

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

Theoretically, black pepper might increase the sedative effects of pentobarbital.
Animal research shows that piperine, a constituent of black pepper, increases pentobarbital-induced sleeping time.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

Black pepper might increase blood levels of phenytoin.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption, slow elimination, and increase levels of phenytoin. Taking a single dose of black pepper 1 gram along with phenytoin seems to double the serum concentration of phenytoin. Consuming a soup with black pepper providing piperine 44 mg/200 mL of soup along with phenytoin also seems to increase phenytoin levels when compared with consuming the same soup without black pepper.

Likelihood Possible Evidence B
Propranolol (Inderal)

Black pepper might increase blood levels of propranolol.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of propranolol.

Likelihood Possible Evidence B
Rifampin (Rifadin)

Black pepper might increase blood levels of rifampin.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and serum levels of rifampin.

Likelihood Possible Evidence B
Theophylline

Black pepper might increase blood levels of theophylline.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of theophylline.

Likelihood Possible Evidence D
Amoxicillin (Amoxil, Trimox)

Theoretically, black pepper might increase the effects and side effects of amoxicillin.
Animal research shows that taking piperine, a constituent of black pepper, with amoxicillin increases plasma levels of amoxicillin. This has not been reported in humans.

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

Theoretically, black pepper might increase blood levels of carbamazepine, potentially increasing the effects and side effects of carbamazepine.
One clinical study in patients taking carbamazepine 300 mg or 500 mg twice daily shows that taking a single 20 mg dose of purified piperine, a constituent of black pepper, increases carbamazepine levels. Piperine may increase carbamazepine absorption by increasing blood flow to the GI tract, increasing the surface area of the small intestine, or inhibiting cytochrome P450 3A4 (CYP3A4) in the gut wall. Absorption was significantly increased by 7-10 mcg/mL/hour. The time to eliminate carbamazepine was also increased by 4-8 hours. Although carbamazepine levels were increased, this did not appear to increase side effects. In vitro research also shows that piperine can increase carbamazepine levels by 11% in a time-dependent manner.

Likelihood Possible Evidence B
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, black pepper might decrease levels and clinical effects of drugs metabolized by CYP1A2.
In vitro research suggests that black pepper induces CYP1A2. This has not been reported in humans.

Likelihood Possible Evidence D
Bioperine Nature's Thermonutrient full monograph & interactions

Synephrine HCl13 drug types · 957 drugs

Midazolam (Versed)

Bitter orange might increase blood levels of midazolam.
One small clinical study shows that bitter orange juice can increase midazolam levels, likely through inhibition of cytochrome P450 3A4 (CYP3A4). Theoretically, bitter orange might increase the risk of midazolam-related adverse effects.

Likelihood Probable Evidence B
Monoamine Oxidase Inhibitors (Maois)

Theoretically, taking MAOIs with synephrine-containing bitter orange preparations might increase the hypertensive effects of synephrine, potentially leading to hypertensive crisis.
Bitter orange contains tyramine, octopamine, and synephrine, which are MAO substrates.

Likelihood Probable Evidence D
Antidiabetes Drugs

Theoretically, bitter orange might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Some clinical research shows that drinking a tea containing bitter orange and Indian snakeroot reduces fasting and postprandial glucose levels in patients with type 2 diabetes who are using antidiabetes drugs. However, it is unclear if these effects are due to bitter orange, Indian snakeroot, or the combination. An animal study also shows that p-synephrine in combination with gliclazide , a sulfonylurea, causes an additional 20% to 44% decrease in glucose levels when compared with gliclazide alone.

Likelihood Possible Evidence B
Caffeine

Bitter orange might increase blood pressure and heart rate when taken with caffeine.
Small clinical studies show that taking bitter orange in combination with caffeine can increase blood pressure and heart rate in otherwise healthy normotensive adults. Theoretically, this might increase the risk of serious cardiovascular adverse effects.

Likelihood Possible Evidence B
Colchicine

Bitter orange might affect colchicine levels.
Colchicine is a substrate of P-glycoprotein and cytochrome P450 3A4 (CYP3A4). Bitter orange has been reported to inhibit CYP3A4 and increase levels of CYP3A4 substrates. However, one small clinical study in healthy adults shows that drinking bitter orange juice 240 mL twice daily for 4 days and taking a single dose of colchicine 0.6 mg on the 4th day decreases colchicine peak serum levels by 24%, time to peak serum level by 1 hour, and overall exposure to colchicine by 20%. The clinical significance of this finding is unclear.

Likelihood Possible Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Bitter orange might increase levels of drugs metabolized by CYP3A4.
Small clinical studies suggest that single or multiple doses of freshly squeezed bitter orange juice 200-240 mL can inhibit CYP3A4 metabolism of drugs, causing increased drug levels and potentially increasing the risk of adverse effects. However, the extent of the effect of bitter orange on CYP3A4-mediated drug interactions is unknown. Some evidence suggests that bitter orange selectively inhibits intestinal CYP3A4, but not hepatic CYP3A4. Its effect on P-glycoprotein, which strongly overlaps with CYP3A4 interactions, is unclear. One small clinical study shows that drinking 8 ounces of freshly squeezed bitter orange juice has no effect on cyclosporine, which seems to be more dependent on hepatic CYP3A4 and P-glycoprotein than intestinal CYP3A4.

Likelihood Possible Evidence B
Dextromethorphan (Robitussin Dm, Others)

Bitter orange might increase blood levels of dextromethorphan.
One small clinical study shows that bitter orange juice increases dextromethorphan levels, likely through cytochrome P450 3A4 (CYP3A4) inhibition. Theoretically, bitter orange might increase the risk for dextromethorphan-related adverse effects.

Likelihood Possible Evidence B
Felodipine (Plendil)

Bitter orange might increase blood levels of felodipine.
One small clinical study shows that bitter orange juice increases felodipine levels, likely through cytochrome P450 3A4 (CYP3A4) inhibition. Theoretically, bitter orange might increase the risk for felodipine-related adverse effects.

Likelihood Probable Evidence B
Indinavir (Crixivan)

Bitter orange might increase blood levels of indinavir.
One small clinical study shows that bitter orange juice slightly increases indinavir levels, but this effect is likely to be clinically insignificant. Bitter orange selectively inhibits intestinal cytochrome P450 3A4 (CYP3A4); however, the metabolism of indinavir seems to be more dependent on hepatic CYP3A4. The effect of bitter orange on other protease inhibitors has not been studied.

Likelihood Possible Evidence B
Qt Interval-Prolonging Drugs

Theoretically, bitter orange might have an additive effect when combined with drugs that prolong the QT interval, potentially increasing the risk of ventricular arrhythmias.
One case report suggests that taking bitter orange in combination with other stimulants such as caffeine might prolong the QT interval in some patients.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Bitter orange juice might increase blood levels of sildenafil.
A small clinical study in healthy adult males shows that drinking freshly squeezed bitter orange juice 250 mL daily for 3 days and taking a single dose of sildenafil 50 mg on the 3rd day increases the peak plasma concentration of sildenafil by 18% and the overall exposure to sildenafil by 44%. Theoretically, this may be due to inhibition of cytochrome P450 3A4 by bitter orange.

Likelihood Probable Evidence B
Stimulant Drugs

Theoretically, bitter orange might increase the risk of hypertension and adverse cardiovascular effects when taken with stimulant drugs.
Bitter orange appears to have stimulant effects.

Likelihood Possible Evidence B
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, bitter orange might increase levels of drug metabolized by CYP2D6.
In vitro research shows that octopamine, a constituent of bitter orange, weakly inhibits CYP2D6 enzymes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Synephrine HCl full monograph & interactions

Theobromine37 drug types · 661 drugs

Ace Inhibitors (Aceis)

Theoretically, taking cocoa with ACEIs might increase the risk of adverse effects.
Human research shows that dark chocolate can inhibit ACE. Additionally, prolonged angioedema in an elderly patient on an ACE inhibitor was precipitated with intake of diabetic chocolate.

Likelihood Possible Evidence D
Adenosine (Adenocard)

Theoretically, cocoa might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Cocoa contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. However, methylxanthines appear more likely to interfere with dipyridamole than adenosine-induced stress testing.

Likelihood Possible Evidence B
Alcohol (Ethanol)

Theoretically, concomitant use might increase levels and adverse effects of caffeine.
Cocoa contains caffeine. Alcohol reduces caffeine metabolism. Concomitant use of alcohol can increase caffeine serum concentrations and the risk of caffeine adverse effects.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, cocoa may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Clinical research shows that intake of cocoa can inhibit platelet adhesion, aggregation, and activity and increase aspirin-induced bleeding time. For patients on dual antiplatelet therapy, cocoa may enhance the inhibitory effect of clopidogrel, but not aspirin, on platelet aggregation.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, taking cocoa with antihypertensive drugs might increase the risk of hypotension.
Clinical research shows that cocoa can modestly decrease blood pressure in hypertensive and normotensive patients.

Likelihood Possible Evidence D
Beta-Adrenergic Agonists

Theoretically, large amounts of cocoa might increase the cardiac inotropic effects of beta-agonists.
Cocoa contains caffeine. Theoretically, large amounts of caffeine might increase cardiac inotropic effects of beta-agonists. A case of atrial fibrillation associated with consumption of large quantities of chocolate in a patient with chronic albuterol inhalation abuse has also been reported.

Likelihood Probable Evidence D
Cytochrome P450 1A2 (Cyp1A2) Inhibitors

Theoretically, concomitant use might increase the levels and adverse effects of caffeine.
Cocoa contains caffeine. Caffeine is metabolized by cytochrome P450 1A2 (CYP1A2),. Theoretically, drugs that inhibit CYP1A2 may decrease the clearance rate of caffeine from cocoa and increase caffeine levels.

Likelihood Possible Evidence D
Dipyridamole (Persantine)

Theoretically, cocoa might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Cocoa contains caffeine. Caffeine may inhibit dipyridamole-induced vasodilation. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. Methylxanthines appear more likely to interfere with dipyridamole than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram might increase the risk of adverse effects from caffeine.
Cocoa contains caffeine. In human research, disulfiram decreases the rate of caffeine clearance.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, using cocoa with diuretic drugs might increase the risk of hypokalemia.
Cocoa contains caffeine. In excessive amounts, caffeine can reduce potassium levels due to stimulation of the sodium-potassium pump. Diuretics can also cause lower potassium levels.

Likelihood Possible Evidence D
Ephedrine

Theoretically, concomitant use might increase the risk for stimulant adverse effects.
Cocoa contains caffeine. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death.

Likelihood Possible Evidence D
Estrogens

Theoretically, estrogens might increase the levels and adverse effects of caffeine.
Cocoa contains caffeine. Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Flutamide (Eulexin)

Theoretically, cocoa might increase the levels and adverse effects of flutamide.
Cocoa contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide.

Likelihood Possible Evidence D
Fluvoxamine (Luvox)

Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
Cocoa contains caffeine. Fluvoxamine reduces caffeine metabolism.

Likelihood Probable Evidence D
Lithium

Theoretically, abrupt cocoa withdrawal might increase the levels and adverse effects of lithium.
Cocoa contains caffeine. There are two case reports of lithium tremor that worsened upon abrupt coffee withdrawal.

Likelihood Possible Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk of a hypertensive crisis.
Cocoa contains caffeine. Large amounts of caffeine with MAOIs might precipitate a hypertensive crisis.

Likelihood Possible Evidence D
Nicotine

Theoretically, concomitant use might increase the risk of hypertension.
Cocoa contains caffeine. Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly.

Likelihood Probable Evidence B
Pentobarbital (Nembutal)

Theoretically, cocoa might decrease the effects of pentobarbital.
Cocoa contains caffeine. Caffeine might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

Theoretically, cocoa might reduce the effects of phenobarbital and increase the risk for convulsions.
Cocoa contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenobarbital. The exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Phenylpropanolamine

Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.
Cocoa contains caffeine. Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure. Phenylpropanolamine also seems to increase caffeine serum levels.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, cocoa might reduce the effects of phenytoin and increase the risk for convulsions.
Cocoa contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenytoin. The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Quinolone Antibiotics

Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.
Cocoa contains caffeine. Quinolones (also referred to as fluoroquinolones) decrease caffeine clearance.

Likelihood Probable Evidence B
Riluzole (Rilutek)

Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.
Cocoa contains caffeine. Caffeine and riluzole are both metabolized by cytochrome P450 1A2, and concomitant use might reduce metabolism of one or both agents.

Likelihood Possible Evidence D
Stimulant Drugs

Theoretically, concomitant use might increase stimulant adverse effects.
Cocoa contains caffeine. Concomitant use might increase the risk of stimulant adverse effects.

Likelihood Probable Evidence C
Theophylline

Theoretically, cocoa might increase the levels and adverse effects of theophylline.
Cocoa contains caffeine. Large amounts of caffeine might inhibit theophylline metabolism. Caffeine decreases theophylline clearance 23% to 29%.

Likelihood Probable Evidence B
Theobromine full monograph & all 37 interactions

Caffeine Anhydrous41 drug types · 655 drugs

Ephedrine

Theoretically, concomitant use might increase the risk for stimulant adverse effects.
Use of ephedrine with caffeine can increase the risk of stimulatory adverse effects. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death.

Likelihood Probable Evidence D
Adenosine (Adenocard)

Theoretically, caffeine might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Some evidence shows that caffeine is a competitive inhibitor of adenosine and can reduce the vasodilatory effects of adenosine in humans. However, other research shows that caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Possible Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, caffeine may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Caffeine is reported to have antiplatelet activity. Theoretically, it might increase the risk of bleeding when used concomitantly with these agents; however, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Beta-Adrenergic Agonists

Theoretically, large amounts of caffeine might increase the cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Carbamazepine (Tegretol)

Theoretically, caffeine might reduce the effects of carbamazepine and increase the risk for convulsions.
Animal research suggests that taking caffeine can lower the anticonvulsant effects of carbamazepine and can induce seizures when taken in doses above 400 mg/kg. Human research has shown that taking caffeine 300 mg in three divided doses along with carbamazepine 200 mg reduces the bioavailability of carbamazepine by 32% and prolongs the plasma half-life of carbamazepine 2-fold in healthy individuals.

Likelihood Possible Evidence D
Cimetidine (Tagamet)

Theoretically, cimetidine might increase the levels and adverse effects of caffeine.
Cimetidine decreases the rate of caffeine clearance by 31% to 42%.

Likelihood Likely Evidence B
Clozapine (Clozaril)

Caffeine might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Caffeine might increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg per day inhibit clozapine metabolism. Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Although researchers speculate that caffeine might inhibit CYP1A2, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients more sensitive to an interaction between clozapine and caffeine. In one case report, severe, life-threatening clozapine toxicity and multiorgan system failure occurred in a patient with schizophrenia stabilized on clozapine who consumed caffeine 600 mg daily.

Likelihood Possible Evidence B
Dipyridamole (Persantine)

Theoretically, caffeine might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Caffeine inhibits dipyridamole-induced vasodilation. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. Methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram use might increase the levels and adverse effects of caffeine.
Disulfiram decreases the rate of caffeine clearance.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, using caffeine with diuretic drugs might increase the risk of hypokalemia.
Caffeine, especially in excessive amounts, can reduce potassium levels due to stimulation of the sodium-potassium pump. Diuretics can also cause lower potassium levels.

Likelihood Possible Evidence D
Estrogens

Theoretically, estrogens might increase the levels and adverse effects of caffeine.
Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Ethosuximide (Zarontin)

Theoretically, caffeine might reduce the effects of ethosuximide and increase the risk for convulsions.
Animal research suggests that caffeine 92.4 mg/kg can decrease the anticonvulsant activity of ethosuximide. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Felbamate (Felbatol)

Theoretically, caffeine might reduce the effects of felbamate and increase the risk for convulsions.
Animal research suggests that a high dose of caffeine 161.7 mg/kg can decreases the anticonvulsant activity of felbamate. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Flutamide (Eulexin)

Theoretically, caffeine might increase the levels and adverse effects of flutamide.
In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide. However, this effect has not been reported in humans.

Likelihood Probable Evidence D
Fluvoxamine (Luvox)

Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
Fluvoxamine reduces caffeine metabolism.

Likelihood Probable Evidence D
Lithium

Abrupt caffeine withdrawal might increase the levels and adverse effects of lithium.
Caffeine has diuretic activity. When abruptly discontinued, caffeine may alter the clearance of lithium. There are two case reports of lithium tremor that worsened upon abrupt coffee withdrawal and 6 case reports of elevated serum lithium levels after reducing or eliminating caffeine intake. In one case, a male with schizoaffective disorder stabilized on lithium had an elevated lithium level after reducing his caffeine intake by 87%. At a later date, he increased his caffeine intake by 6-fold, resulting in a subtherapeutic lithium level and a recurrence of psychiatric symptoms.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk of a hypertensive crisis.
Caffeine has been shown to inhibit monoamine oxidase (MAO) A and B in laboratory studies. Concomitant intake of large amounts of caffeine with MAOIs might precipitate a hypertensive crisis. In a case report, a patient that consumed 10-12 cups of caffeinated coffee and took the MAOI tranylcypromine presented with severe hypertension. Hypertension was resolved after the patient switched to drinking decaffeinated coffee.

Likelihood Possible Evidence D
Nicotine

Theoretically, concomitant use might increase the risk of hypertension.
Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly.

Likelihood Probable Evidence B
Pentobarbital (Nembutal)

Theoretically, caffeine might decrease the effects of pentobarbital.
Caffeine might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

Theoretically, caffeine might reduce the effects of phenobarbital and increase the risk for convulsions.
Animal research suggests that caffeine can decrease the anticonvulsant activity of phenobarbital. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Phenylpropanolamine

Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.
Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure. Phenylpropanolamine also seems to increase caffeine serum levels.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, caffeine might reduce the effects of phenytoin and increase the risk for convulsions.
Animal research suggests that caffeine can decrease the anticonvulsant activity of phenytoin. The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Pioglitazone (Actos)

Theoretically, caffeine might increase the levels and clinical effects of pioglitazone.
Animal research suggests that caffeine can modestly increase the maximum concentration, area under the curve, and half-life of pioglitazone, and also reduce its clearance. This increased the antidiabetic effects of pioglitazone. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Quinolone Antibiotics

Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.
Quinolones (also called fluoroquinolones) can decrease caffeine clearance by inhibiting cytochrome P450 1A2 (CYP1A2) enzyme.

Likelihood Probable Evidence B
Riluzole (Rilutek)

Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.
Caffeine and riluzole are both metabolized by cytochrome P450 1A2 (CYP1A2), and concomitant use might reduce the metabolism of one or both agents.

Likelihood Possible Evidence D
Caffeine Anhydrous full monograph & all 41 interactions

L-Theanine3 drug types · 565 drugs

Antihypertensive Drugs

Theanine might lower blood pressure, potentiating the effects of antihypertensive drugs.
Animal research shows that theanine can lower blood pressure in spontaneously hypertensive animals. Theoretically, concomitant use of theanine and antihypertensive drugs might potentiate the antihypertensive activity.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, theanine might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Theoretically, theanine may compete with glutamate and/or increase plasma gamma-aminobutyric acid (GABA) levels, which could cause CNS depression. In one clinical study, some subjects taking oral theanine reported drowsiness.

Likelihood Unlikely Evidence D
Serotonergic Drugs

Clinical studies regarding the effects of L-theanine on serotonin levels are conflicting. Some studies suggest it can increase serotonin levels in the brain while others report that it may decrease them. Nevertheless, there have been no reports of l-theanine being a causative agent in serotonergic-related side effects or serotonin syndrome.

Likelihood Unlikely Evidence C
L-Theanine full monograph & interactions

Hordenine HCl3 drug types · 329 drugs

Monoamine Oxidase Inhibitors (Maois)

Hordenine is structurally similar to tyramine In vitro research shows that hordenine is a selective substrate for monoamine oxidase-B in the liver. Theoretically, concomitant use of hordenine with MAOIs might increase blood pressure, potentially leading to a hypertensive crisis.
Some MAOIs include isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate).

Likelihood Possible Evidence D
Stimulant Drugs

Hordenine is structurally similar to N-methyltyramine and synephrine, constituents in bitter orange known to have stimulant properties. Theoretically, taking hordenine with drugs with stimulant properties might increase the risk of hypertension and other adverse cardiovascular effects.
Some of these drugs include amphetamine, caffeine, methylphenidate, pseudoephedrine, and many others.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Hordenine weakly inhibits cytochrome P450 2D6 (CYP2D6) enzymes in vitro. Theoretically, hordenine might increase the levels of CYP2D6 substrates.
Some of drugs that are CYP2D6 substrates include amitriptyline (Elavil), clozapine (Clozaril), codeine, desipramine (Norpramin), donepezil (Aricept), fentanyl (Duragesic), flecainide (Tambocor), fluoxetine (Prozac), meperidine (Demerol), methadone (Dolophine), metoprolol (Lopressor, Toprol XL), olanzapine (Zyprexa), ondansetron (Zofran), tramadol (Ultram), trazodone (Desyrel), and others.

Likelihood Possible Evidence D
Hordenine HCl full monograph & interactions

Theacrine1 drug type · 248 drugs

Cns Depressants

Theoretically, theacrine might alter the effects of CNS depressants.
Animal research shows that low doses of theacrine have sedating effects, whereas high doses might have stimulant effects. Depending on the dose of theacrine used, it might increase or decrease the effects of CNS depressants. However, these effects have not yet been reported in humans.

Likelihood Possible Evidence D
Theacrine full monograph & interactions

Huperzine A2 drug types · 219 drugs

Anticholinergic Drugs

Theoretically, huperzine A might decrease the effects of anticholinergic drugs.
Huperzine A has acetylcholinesterase (AChE) inhibiting effects. In animal models, huperzine A reversed cognitive deficits induced by scopolamine, an anticholinergic drug.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, concurrent use of huperzine A with cholinergic drugs might increase the effects and side effects of these medications.
Huperzine A can inhibit acetylcholinesterase (AChE) and might cause cumulative effects if used with cholinergic drugs.

Likelihood Possible Evidence B
Huperzine A full monograph & interactions

Dimethylaminoethanol (DMAE) Bitartrate2 drug types · 219 drugs

Anticholinergic Drugs

Theoretically, deanol might decrease the effectiveness of anticholinergic drugs.
Deanol is thought to increase acetylcholine levels.

Likelihood Unlikely Evidence D
Cholinergic Drugs

Theoretically, deanol might increase the effects and adverse effects of cholinergic drugs.
Deanol is thought to increase acetylcholine levels.

Likelihood Unlikely Evidence D
Dimethylaminoethanol (DMAE) Bitartrate full monograph & interactions

Macuna pruriens8 drug types · 193 drugs

Levodopa

Concomitant use can increase the risk of levodopa-related adverse effects.
Cowhage contains levodopa. Some cowhage products have been standardized to contain 75-400 mg of levodopa per dose.

Likelihood Likely Evidence D
Methyldopa (Aldomet)

Theoretically, concomitant use of cowhage and methyldopa might increase the risk of hypotension.
Cowhage contains levodopa. Use of levodopa with methyldopa might cause additive hypotension. In addition, methyldopa may inhibit peripheral decarboxylation of levodopa and increase levodopa levels in the central nervous system; avoid using.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use of cowhage and non-selective MAOIs might increase the risk of hypertensive crisis.
Cowhage contains levodopa. Use of levodopa with non-selective MAOIs might cause hypertensive crisis. However, this interaction has not been reported with MAO-B selective inhibitors such as selegiline.

Likelihood Probable Evidence D
Anesthesia

Theoretically, concomitant use of cowhage and anesthesia might increase the risk of arrhythmias.
Cowhage contains levodopa. Use of levodopa with cyclopropane or halogenated hydrocarbon anesthesia has led to arrhythmias. Other anesthetics have not been implicated. Use other anesthetics in patients taking cowhage or tell patients to stop taking cowhage at least 2 weeks before surgery.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, concomitant use of cowhage and antidiabetes drugs might increase the risk of hypoglycemia.
Animal research shows that cowhage might have hypoglycemic effects.

Likelihood Possible Evidence D
Antipsychotic Drugs

Theoretically, use of cowhage might decrease the clinical effects of antipsychotic drugs.
Cowhage contains levodopa. Use of levodopa might counteract the antidopaminergic effects of antipsychotic medications.

Likelihood Possible Evidence D
Guanethidine (Ismelin)

Theoretically, concomitant use of cowhage and guanethidine might increase the risk of hypotension.
Cowhage contains levodopa. Use of levodopa with guanethidine might cause additive hypotension; avoid using.

Likelihood Probable Evidence D
Tricyclic Antidepressants (Tcas)

Theoretically, use of TCAs might reduce the levels and clinical effects of cowhage.
Cowhage contains levodopa. Use of TCAs might reduce the absorption of levodopa. Some case reports describe patients that developed hypertension and dyskinesia when taking both levodopa and TCAs.

Likelihood Possible Evidence D
Macuna pruriens full monograph & interactions

L-Tyrosine2 drug types · 21 drugs

Levodopa

Theoretically, tyrosine might decrease the effectiveness of levodopa.
Tyrosine and levodopa compete for absorption in the proximal duodenum by the large neutral amino acid (LNAA) transport system. Advise patients to separate doses of tyrosine and levodopa by at least 2 hours.

Likelihood Probable Evidence D
Thyroid Hormone

Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Tyrosine is a precursor to thyroxine and might increase levels of thyroid hormones.

Likelihood Probable Evidence D
L-Tyrosine full monograph & interactions

Alpha-Glyceryl Phosphoryl Choline1 drug type · 16 drugs

Scopolamine (Transderm Scop)

Theoretically, alpha-GPC might decrease the effects of scopolamine.
A small clinical study shows that alpha-GPC can partially counteract the attention and memory impairment effects caused by scopolamine given intramuscularly. Whether alpha-GPC can decrease the beneficial anti-motion sickness effects of the scopolamine patch (Transderm Scop) is unclear.

Likelihood Possible Evidence B
Alpha-Glyceryl Phosphoryl Choline full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Alphagen Strawberry Lemonade, from the product label.

Morphogen Nutrition

See all Morphogen Nutrition products
Name
Morphogen Nutrition
Web Address
www.mntakeover.com
Pharmacist Counseling Corner

Alphagen Strawberry Lemonade by Morphogen Nutrition: Common Questions

Does Alphagen Strawberry Lemonade by Morphogen Nutrition interact with any medications?
Yes. Based on its ingredients, Alphagen Strawberry Lemonade has a known interaction with 1,540 medications, including 26 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Alphagen Strawberry Lemonade contains 16 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Does this product contain creatine?
Yes, Creatine Monohydrate is in it. Creatine is possibly effective for muscle strength and athletic performance. It's generally well tolerated, though it can cause dehydration, diarrhea, muscle cramps, and water retention in some people.
Will this help me focus and stay alert?
The product contains multiple ingredients aimed at focus and alertness — Caffeine (likely effective for mental alertness), L-Theanine (possibly effective for cognitive function), Huperzine A (possibly effective for cognition), and DMAE. However, evidence is strongest for caffeine; the others have more limited or uncertain evidence.
Is it safe if I'm pregnant or breastfeeding?
No — most ingredients advise against use during pregnancy and breastfeeding due to insufficient safety data or known risks. Creatine and several others should be avoided in pregnancy, and some (like Macuna pruriens) can lower milk supply. Talk to your doctor or pharmacist for personalized advice.
What is that tingling sensation I might feel?
Beta-Alanine in this product commonly causes a harmless tingling sensation (paresthesia) on the scalp and body starting within 20 minutes of the dose, usually lasting about an hour. This is dose-dependent and not dangerous.
Can I take this if I have kidney problems?
Creatine, a key ingredient, requires caution if you have kidney issues. Talk to your doctor or pharmacist before using this product if you have any kidney disease or function problems.
Does this interact with my blood pressure or heart medications?
Yes — several ingredients can affect blood pressure and heart function. Caffeine, Synephrine, and Hordenine are stimulants that can raise blood pressure; L-Theanine can theoretically lower it; and interactions with specific heart drugs are documented. Use the medication checker on this page with your exact prescriptions.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Alphagen Strawberry Lemonade label
Go deeper

The Full Monographs Behind Alphagen Strawberry Lemonade’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Creatine

Creatine is one of the most studied sports supplements, with solid evidence that it can boost strength and performance during short, high-intensity activities like weightlifting and sprintin...

Read the full Creatine monograph → Herb & supplement monograph

Tyrosine

Interacts with 21 drugs

L-tyrosine is an amino acid your body uses to make brain chemicals like dopamine and norepinephrine. Some studies suggest it may help mental performance during short-term stress, sleep loss,...

Read the full Tyrosine monograph → Herb & supplement monograph

Beta-alanine

Beta-alanine is an amino acid taken mostly by athletes to raise muscle carnosine, which may help buffer acid and reduce fatigue during short, high-intensity exercise. The evidence is moderat...

Read the full Beta-alanine monograph → Herb & supplement monograph

Theanine

Interacts with 565 drugs

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong drowsiness. Early research suggests it may...

Read the full Theanine monograph → Herb & supplement monograph

Caffeine

Interacts with 655 drugs

Caffeine is a natural stimulant found in coffee, tea, and many other plants and products. In moderate amounts it can boost alertness and reduce tiredness for most healthy adults, but too muc...

Read the full Caffeine monograph → Herb & supplement monograph

Huperzine A

Interacts with 219 drugs

Huperzine A is a purified compound from a Chinese clubmoss that acts like a mild cholinesterase inhibitor, similar in mechanism to some prescription Alzheimer's drugs. Some small studies sug...

Read the full Huperzine A monograph → Herb & supplement monograph

Bitter Orange

Interacts with 957 drugs

Bitter orange is a citrus fruit whose extracts contain synephrine, a mild stimulant often added to weight-loss and energy supplements. Evidence that it works for weight loss or performance i...

Read the full Bitter Orange monograph → Herb & supplement monograph

Hordenine

Interacts with 329 drugs

Hordenine is a natural alkaloid found in barley and some cacti that is marketed as a stimulant for energy, focus, and fat loss, but solid human evidence for these benefits is lacking. Its sa...

Read the full Hordenine monograph → Herb & supplement monograph

Deanol

Interacts with 219 drugs

Deanol (DMAE) is a compound related to choline that is marketed for memory, focus, and mood, but solid human evidence for most of these uses is limited or mixed. It can cause side effects in...

Read the full Deanol monograph → Herb & supplement monograph

Cowhage

Interacts with 193 drugs

Cowhage (Mucuna pruriens) is a tropical legume best known as a natural source of L-dopa, the compound the body turns into dopamine. It is most studied for Parkinson's disease symptoms and ma...

Read the full Cowhage monograph → Herb & supplement monograph

Alpha-gpc

Interacts with 16 drugs

Alpha-GPC is a choline-containing compound used mainly for memory, brain health, and as a choline source. There is some evidence it may help cognition in people with dementia, but evidence i...

Read the full Alpha-gpc monograph → Herb & supplement monograph

Theacrine

Interacts with 248 drugs

Theacrine is a caffeine-like compound found naturally in certain tea plants and is sold in supplements for energy, focus, and mood. Early human studies suggest it may give a stimulant-like b...

Read the full Theacrine monograph → Herb & supplement monograph

Cocoa

Interacts with 661 drugs

Cocoa is rich in plant compounds called flavanols that may modestly support blood vessel function and blood pressure, but most chocolate products are high in sugar, fat, and calories, which...

Read the full Cocoa monograph → Herb & supplement monograph

Black Pepper

Interacts with 1,019 drugs

Black pepper is a common kitchen spice that is generally safe in the amounts used in food. Its extract, piperine, is mostly added to supplements to help the body absorb other ingredients (li...

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Sources

Sources & How We Checked

Alphagen Strawberry Lemonade's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 588 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Creatine 86 references
  1. Koshy KM, Griswold E, Schneeberger EE. Interstitial nephritis in a patient taking creatine. N Engl J Med 1999;340:814-5. PubMed
  2. Vahedi K, Domingo V, Amarenco P, Bousser MG. Ischemic stroke in a sportsman who consumed MaHuang extract and creatine monohydrate for bodybuilding. J Neurol Neurosurg Psychiatr 2000;68:112-3.
  3. Greenhaff P. Renal dysfunction accompanying oral creatine supplements. Lancet 1998;352:233-4. PubMed
  4. Vandenberghe K, Goris M, Van Hecke P, et al. Long-term creatine intake is beneficial to muscle performance during resistance training (abstract). J Appl Physiol 1997;83:2055-63. PubMed
  5. Hultman E, Soderlund K, Timmons JA, et al. Muscle creatine loading in men. J Appl Physiol 1996;81:232-7. PubMed
  6. Pritchard NR, Kalra PA. Renal dysfunction accompanying oral creatine supplements. Lancet 1998;351:1252-3. PubMed
  7. Poortmans JR, Auquier H, Renaut V, et al. Effect of short-term creatine supplementation on renal responses in men (abstract). Eur J Appl Physiol Occup Physiol 1997;76:566-7. PubMed
  8. Poortmans JR, Francaux M. Long-term oral creatine supplementation does not impair renal function in healthy athletes. Med Sci Sports Exerc 1999;31:1108-10. PubMed
  9. Mihic S, MacDonald JR, McKenzie S, Tarnopolsky MA. Acute creatine loading increases fat-free mass, but does not affect blood pressure, plasma creatinine, or CK activity in men and women. Med Sci Sports Exerc 2000;32:291-6. PubMed
  10. Rawson ES, Wehnert ML, Clarkson PM. Effects of 30 days of creatine ingestion in older men. Eur J Appl Physiol Occup Physiol 1999;80:139-44. PubMed
  11. Earnest CP, Almada AL, Mitchell TL. High-performance capillary electrophoresis-pure creatine monohydrate reduces blood lipids in men and women. Clin Sci (Colch) 1996;91:113-8. PubMed
  12. Juhn MS. Oral creatine supplementation. Separating fact from hype. Phys Sportsmed 1999;27:47-50,53-54,56,61,89. PubMed
  13. Juhn MS, O'Kane JW, Vinci DM. Oral creatine supplementation in male collegiate athletes: a survey of dosing habits and side effects. J Am Diet Assoc 1999;99:593-5.
  14. Green AL, Hultman E, Macdonald IA, et al. Carbohydrate ingestion augments skeletal muscle creatine accumulation during creatine supplementation in humans. Am J Physiol 1996;271:E821-6. PubMed
  15. Balsom PD, Soderlund K, Sjodin B, Ekblom B. Skeletal muscle metabolism during short duration high-intensity exercise: influence of creatine supplementation. Acta Physiol Scand 1995;154:303-10. PubMed
  16. Snow RJ, McKenna MJ, Selig SE, et al. Effect of creatine supplementation on sprint exercise performance and muscle metabolism. (abstract) J Appl Physiol 1998;84:1667-73. PubMed
  17. McNaughton LR, Dalton B, Tarr J. The effects of creatine supplementation on high-intensity exercise performance in elite performers. (abstract) Eur J Appl Physiol Occup Physiol 1998;78:236-40. PubMed
  18. Groeneveld GJ, Veldink JH, van der Tweel I, et al. A randomized sequential trial of creatine in amyotrophic lateral sclerosis. Ann Neurol 2003;53:437-45. . PubMed
  19. Robinson SJ. Acute quadriceps compartment syndrome and rhabdomyolysis in a weight lifter using high-dose creatine supplementation. J Am Board Fam Pract 2000;13:134-7. PubMed
  20. Kammer RT. Lone atrial fibrillation associated with creatine monohydrate supplementation. Pharmacotherapy 2005;25:762-4. PubMed
  21. Gualano B, Ugrinowitsch C, Novaes RB, et al. Effects of creatine supplementation on renal function: a randomized, double-blind, placebo-controlled clinical trial. Eur J Appl Physiol 2008;103:33-40. PubMed
  22. Pfeffer, G., Majamaa, K., Turnbull, D. M., Thorburn, D., and Chinnery, P. F. Treatment for mitochondrial disorders. Cochrane Database.Syst.Rev. 2012;4:CD004426. PubMed
  23. Boos, C. J., White, S. H., Bland, S. A., and McAllister, P. D. Dietary supplements and military operations: caution is advised. J R.Army Med Corps 2010;156(1):41-43. PubMed
  24. Kreider, R. B. Dietary supplements and the promotion of muscle growth with resistance exercise. Sports Med 1999;27(2):97-110. PubMed
  25. Juhn, M. S., O'Kane, J. W., and Vinci, D. M. Oral creatine supplementation in male collegiate athletes: a survey of dosing habits and side effects. J Am.Diet.Assoc 1999;99(5):593-595.
  26. Volek, J. S., Duncan, N. D., Mazzetti, S. A., Putukian, M., Gomez, A. L., and Kraemer, W. J. No effect of heavy resistance training and creatine supplementation on blood lipids. Int J Sport Nutr.Exerc.Metab 2000;10(2):144-156. PubMed
  27. Robinson, T. M., Sewell, D. A., Casey, A., Steenge, G., and Greenhaff, P. L. Dietary creatine supplementation does not affect some haematological indices, or indices of muscle damage and hepatic and renal function. Br.J Sports Med 2000;34(4):284-288. PubMed
  28. Tarnopolsky, M. A. Potential benefits of creatine monohydrate supplementation in the elderly. Curr.Opin.Clin Nutr.Metab Care 2000;3(6):497-502. PubMed
  29. Tarnopolsky, M. A. and MacLennan, D. P. Creatine monohydrate supplementation enhances high-intensity exercise performance in males and females. Int J Sport Nutr.Exerc.Metab 2000;10(4):452-463. PubMed
  30. Arciero, P. J., Hannibal, N. S., III, Nindl, B. C., Gentile, C. L., Hamed, J., and Vukovich, M. D. Comparison of creatine ingestion and resistance training on energy expenditure and limb blood flow. Metabolism 2001;50(12):1429-1434. PubMed
  31. Chrusch, M. J., Chilibeck, P. D., Chad, K. E., Davison, K. S., and Burke, D. G. Creatine supplementation combined with resistance training in older men. Med Sci.Sports Exerc. 2001;33(12):2111-2117. PubMed
  32. Cox, G., Mujika, I., Tumilty, D., and Burke, L. Acute creatine supplementation and performance during a field test simulating match play in elite female soccer players. Int J Sport Nutr.Exerc.Metab 2002;12(1):33-46. PubMed
  33. Kilduff, L. P., Vidakovic, P., Cooney, G., Twycross-Lewis, R., Amuna, P., Parker, M., Paul, L., and Pitsiladis, Y. P. Effects of creatine on isometric bench-press performance in resistance-trained humans. Med Sci.Sports Exerc. 2002;34(7):1176-1183. PubMed
  34. Brose, A., Parise, G., and Tarnopolsky, M. A. Creatine supplementation enhances isometric strength and body composition improvements following strength exercise training in older adults. J Gerontol A Biol.Sci.Med Sci. 2003;58(1):11-19. PubMed
  35. Volek, J. S., Ratamess, N. A., Rubin, M. R., Gomez, A. L., French, D. N., McGuigan, M. M., Scheett, T. P., Sharman, M. J., Hakkinen, K., and Kraemer, W. J. The effects of creatine supplementation on muscular performance and body composition responses to
  36. Tyler, T. F., Nicholas, S. J., Hershman, E. B., Glace, B. W., Mullaney, M. J., and McHugh, M. P. The effect of creatine supplementation on strength recovery after anterior cruciate ligament (ACL) reconstruction: a randomized, placebo-controlled, double-b DOI
  37. Groeneveld, G. J., Beijer, C., Veldink, J. H., Kalmijn, S., Wokke, J. H., and van den Berg, L. H. Few adverse effects of long-term creatine supplementation in a placebo-controlled trial. Int J Sports Med 2005;26(4):307-313. PubMed
  38. Astorino, T. A., Marrocco, A. C., Gross, S. M., Johnson, D. L., Brazil, C. M., Icenhower, M. E., and Kneessi, R. J. Is running performance enhanced with creatine serum ingestion? J Strength.Cond.Res 2005;19(4):730-734. PubMed
  39. Cramer, J. T., Stout, J. R., Culbertson, J. Y., and Egan, A. D. Effects of creatine supplementation and three days of resistance training on muscle strength, power output, and neuromuscular function. J Strength.Cond.Res 2007;21(3):668-677. PubMed
  40. Young, P., De, Jonghe P., Stogbauer, F., and Butterfass-Bahloul, T. Treatment for Charcot-Marie-Tooth disease. Cochrane.Database.Syst.Rev. 2008;(1):CD006052. PubMed
  41. Ostojic, S. M. and Ahmetovic, Z. Gastrointestinal distress after creatine supplementation in athletes: are side effects dose dependent? Res.Sports Med. 2008;16(1):15-22. PubMed
  42. Whitt, K. N., Ward, S. C., Deniz, K., Liu, L., Odin, J. A., and Qin, L. Cholestatic liver injury associated with whey protein and creatine supplements. Semin.Liver Dis. 2008;28(2):226-231. PubMed
  43. Koenig CA, Benardot D Cody M Thompson WR. Comparison of creatine monohydrate and carbohydrate supplementation on repeated jump height performance. J Strength Cond Res. 2008;22(4):1081-1086. PubMed
  44. Gordon, P. H., Cheung, Y. K., Levin, B., Andrews, H., Doorish, C., Macarthur, R. B., Montes, J., Bednarz, K., Florence, J., Rowin, J., Boylan, K., Mozaffar, T., Tandan, R., Mitsumoto, H., Kelvin, E. A., Chapin, J., Bedlack, R., Rivner, M., McCluskey, L.
  45. Bender, A., Samtleben, W., Elstner, M., and Klopstock, T. Long-term creatine supplementation is safe in aged patients with Parkinson disease. Nutr.Res. 2008;28(3):172-178. PubMed
  46. Parness, J. You're "hot" from pumping iron? Anesth.Analg. 2009;108(3):711-713. PubMed
  47. Gualano, B., Ferreira, D. C., Sapienza, M. T., Seguro, A. C., and Lancha, A. H., Jr. Effect of short-term high-dose creatine supplementation on measured GFR in a young man with a single kidney. Am.J.Kidney Dis. 2010;55(3):e7-e9. PubMed
  48. Saidi, H. and Mani, M. Severe metabolic acidosis secondary to coadministration of creatine and metformin, a case report. Am.J.Emerg.Med. 2010;28(3):388-6. PubMed
  49. Gualano, B., de, Salles Painelli, V, Roschel, H., Lugaresi, R., Dorea, E., Artioli, G. G., Lima, F. R., da Silva, M. E., Cunha, M. R., Seguro, A. C., Shimizu, M. H., Otaduy, M. C., Sapienza, M. T., da Costa, Leite C., Bonfa, E., and Lancha Junior, A. H.
  50. Neves, M., Jr., Gualano, B., Roschel, H., Lima, F. R., Lucia, de Sa-Pinto, Seguro, A. C., Shimizu, M. H., Sapienza, M. T., Fuller, R., Lancha, A. H., Jr., and Bonfa, E. Effect of creatine supplementation on measured glomerular filtration rate in postmeno
  51. Gufford, B. T., Sriraghavan, K., Miller, N. J., Miller, D. W., Gu, X., Vennerstrom, J. L., and Robinson, D. H. Physicochemical characterization of creatine N-methylguanidinium salts. J.Diet.Suppl 2010;7(3):240-252.
  52. Lugaresi, R., Leme, M., de, Salles Painelli, V, Murai, I. H., Roschel, H., Sapienza, M. T., Lancha Junior, A. H., and Gualano, B. Does long-term creatine supplementation impair kidney function in resistance-trained individuals consuming a high-protein di
  53. Poortmans, J. R. and Francaux, M. Renal dysfunction accompanying oral creatine supplements. Lancet 7-18-1998;352(9123):234. PubMed
  54. Maganaris, C. N. and Maughan, R. J. Creatine supplementation enhances maximum voluntary isometric force and endurance capacity in resistance trained men. Acta Physiol Scand. 1998;163(3):279-287. PubMed
  55. Vandebuerie, F., Vanden Eynde, B., Vandenberghe, K., and Hespel, P. Effect of creatine loading on endurance capacity and sprint power in cyclists. Int J Sports Med 1998;19(7):490-495. PubMed
  56. Juhn, M. S. and Tarnopolsky, M. Oral creatine supplementation and athletic performance: a critical review. Clin J Sport Med 1998;8(4):286-297. PubMed
  57. Vandenberghe K, Van Hecke P, Van Leemputte M, and et al. Inhibition of muscle phosphocreatine resynthesis by caffeine after creatine loading. Med Sci Sports Exerc 1997;29(5 Supplement):249.
  58. Ziegenfuss T, Lowery LM, and Lemon PW. Acute fluid volume changes in men during three days of creatine supplementation. J Exerc Physiol Online 1998;1(3): .
  59. Kuehl K, Goldberg L, and Elliot D. Renal insufficiency after creatine supplementation in a college football athlete. Med Sci Sports Exerc 1998;30(5 Suppl ):S235. DOI
  60. Balsom PD, Ekblom B, Soderlund K, and et al. Creatine supplementation and dynamic high-intensity intermittent excercise. Scand J Med Sci Sports 1993;3:143-149.
  61. Kirksey KB, Warren BJ, Stone MH, and et al. The effects of six weeks of creatine monohydrate supplementation in male and female track athletes. Med Sci Sports Exerc 1997;29(5 Suppl):S145.
  62. Kreider R, Ransom J, Rasmussen C, and et al. Creatine supplementation during pre-season football does not affect markers of renal function. 83rd Annual Experimental Biology Meeting 1999;
  63. Rasmussen C, Kreider R, Ransom J, and et al. Creatine supplementation during pre-season football training does not affect fluid or electrolyte status. 46th Annual American College of Sports Medicine Annual Meeting 1999; DOI
  64. Tan CW, Hae Tha M, Joo Ng H. Creatine supplementation and venous thrombotic events. Am J Med 2014;127(8):e7-8. PubMed
  65. Young C, Oladipo O, Frasier S, et al. Hemorrhagic stroke in young healthy male following use of sports supplement Jack3d. Mil Med 2012;177(12):1450-4. PubMed
  66. Vilella AL, Limsuwat C, Williams DR, Seifert CF. Cholestatic jaundice as a result of combination designer supplement ingestion. Ann Pharmacother 2013;47(7-8):e33. PubMed
  67. Li N, Hauser R, Holford T, et al. Muscle-building supplement use and increased risk of testicular germ cell cancer in men from Connecticut and Massachusetts. Br J Cancer 2015;112(7):1247-50. PubMed
  68. Centers for Disease Control and Prevention (CDC). Hyperthermia and dehydration-related deaths associated with rapid weight loss in three collegiate wrestlers - North Carolina, Wisconsin, and Michigan, November-December 1997. MMWR Morb Mortal Wkly Rep 1998
  69. Litsky F. Collegiate wrestling deaths raise fears about training. The New York Times. December 19, 1997. Available at: http://www.nytimes.com/1997/12/19/sports/wrestling-collegiate-wrestling-deaths-raise-fears-about-training.html.
  70. The Associated Press. Creatine ruled out in athletes' deaths. The New York Times. May 2, 1998. Available at: http://www.nytimes.com/1998/05/02/sports/plus-college-wrestling-creatine-ruled-out-in-athletes-deaths.html.
  71. Creatine in the dock. Men's Fitness Magazine (Australia). September 2013. Available at: http://www.mensfitnessmagazine.com.au/2013/09/creatine-in-the-dock/.
  72. Galvan E, Walker Dk, Simbo SY, et al. Acute and chronic safety and efficacy of dose dependent creatine nitrate supplementation and exercise performance. J Int Soc Sports Nutr. 2016 Mar 31;13:12. PubMed
  73. Deminice R, Rosa FT, Pfrimer K, Ferrioli E, Jorao AA, Freitas E. Creatine supplementation increases total body water in soccer players: a deuterium oxide dilution study. Int J Sports Med. 2016 Feb;37(2):149-53. PubMed
  74. Wilkinson TJ, Lemmy AB, Jones AG, et al. Can creatine supplementation improve body composition and objective physical function in Rheumatoid Arthritis patients? A randomized controlled trial. Arthritis Care Res (Hoboken). 2016 Jun;68(6):729-37. PubMed
  75. Kreider RB, Kalman DS, Antonio J, et al. International Society of Sports Nutrition position stand: safety and efficacy of creating supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 2017;14:18.
  76. de Guingand DL, Palmer KR, Snow RJ, Davies-Tuck ML, Ellery SJ. Risk of adverse outcomes in females taking oral creatine monohydrate: a systematic review and meta-analysis. Nutrients. 2020;12(6):E1780. PubMed
  77. Almeida D, Colombini A, Machado M. Creatine supplementation improves performance, but is it safe? Double-blind placebo-controlled study. J Sports Med Phys Fitness. 2020;60(7):1034-9. PubMed
  78. Mills S, Candow DG, Forbes SC, Neary JP, Ormsbee MJ, Antonio J. Effects of creatine supplementation during resistance training sessions in physically active young adults. Nutrients. 2020;12(6):1880. PubMed
  79. Whinton AK, Donahoe K, Gao R, et al. Repeated application of a novel creatine cream improves muscular peak and average power in male subjects. J Strength Cond Res. 2020;34(9):2482-2491. PubMed
  80. Dover S, Stephens S, Schneiderman JE, et al. The effect of creatine supplementation on muscle function in childhood myositis: A randomized, double-blind, placebo-controlled feasibility study. J Rheumatol. 2020:jrheum.191375. PubMed
  81. Chilibeck PD, Candow DG, Landeryou T, Kaviani M, Paus-Jenssen L. Effects of creatine and resistance training on bone health in postmenopausal women. Med Sci Sports Exerc. 2015;47(8):1587-95. PubMed
  82. Forbes SC, Candow DG, Ostojic SM, Roberts MD, Chilibeck PD. Meta-analysis examining the importance of creatine ingestion strategies on lean tissue mass and strength in older adults. Nutrients 2021;13(6):1912. PubMed
  83. Silva C, Fung AWS, Masson V, et al. Vitamin D toxicity from an unusual and unexpected source: a report of 2 cases. Horm Res Paediatr 2022. PubMed
  84. Delpino FM, Figueiredo LM, Forbes SC, Candow DG, Santos HO. Influence of age, sex, and type of exercise on the efficacy of creatine supplementation on lean body mass: A systematic review and meta-analysis of randomized clinical trials. Nutrition 2022;103- PubMed
  85. Todorovic N, Korovljev D, Stajer V, Jorga J, Ostojic SM. Creatine consumption and liver disease manifestations in individuals aged 12?years and over. Food Sci Nutr 2022;11(2):1134-1141. PubMed
  86. Robles EL, Pache KM, Gluck JS. Acute compartment syndrome of the leg caused by cocaine use, creatine supplementation and vigorous exercise. J Surg Case Rep 2022;2022(11):rjac502. PubMed

See these in context on the Creatine monograph →

Tyrosine 4 references
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See these in context on the Tyrosine monograph →

Beta-alanine 13 references
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  10. Stellingwerff T, Anwander H, Egger A, et al. Effect of two ß-alanine dosing protocols on muscle carnosine synthesis and washout. Amino Acids 2012;42(6):2461-72. PubMed
  11. da Silva RP, de Oliveira LF, Saunders B, et al. Effects of ß-alanine and sodium bicarbonate supplementation on the estimated energy system contribution during high-intensity intermittent exercise. Amino Acids. 2019;51(1):83-96. PubMed
  12. Varanoske AN, Hoffman JR, Church DD, et al. Comparison of sustained-release and rapid-release ß-alanine formulations on changes in skeletal muscle carnosine and histidine content and isometric performance following a muscle-damaging protocol. Amino Acids. PubMed
  13. Perim P, Gobbi N, Duarte B, et al. Beta-alanine did not improve high-intensity performance throughout simulated road cycling. Eur J Sport Sci 2021. PubMed

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Theanine 6 references
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Caffeine 236 references
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Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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