Major interaction on record — check this product against your medications before combining. Based on 3 of 5 ingredients. Check your meds →
Dietary supplement

Pre-Workout Tropical Candy Ingredients & Drug Interactions

by Outwork Nutrition

Pre-Workout Tropical Candy 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 Pre-Workout Tropical Candy 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

Pre-Workout Tropical Candy is a dietary supplement by Outwork Nutrition with 5 active ingredients. Its ingredients are commonly taken for athletic performance and endurance, high-intensity exercise capacity, reducing muscle fatigue.Based on those ingredients, 1,452 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Rhodiola root extract, Caffeine Anhydrous. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Pre-Workout Tropical Candy by Outwork Nutrition

Ask about any prescription or over-the-counter medication and we check it for interactions with Pre-Workout Tropical Candy by Outwork 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 Pre-Workout Tropical Candy by Outwork 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 11, 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 5 of its 5 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This pre-workout powder has 5 active ingredients. CarnoSyn (beta-alanine) is included to support athletic and physical performance during exercise.

Caffeine anhydrous is a stimulant for mental alertness and athletic performance. Citrulline malate and L-dihydroxyphenylalanine are also present—we don't have effectiveness data on file for these in a pre-workout context.

Rhodiola root extract rounds out the formula. The powder also contains inactive ingredients like citric acid, malic acid, flavoring, sucralose, and anti-caking agents.

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: Athletic performance and exercise capacity.
  • We looked for evidence on: Athletic performance, Physical performance, Exercise-induced muscle breakdown, Exercise-induced muscle soreness, Chronic fatigue syndrome (CFS), 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: Beta-alanine is rated "Possibly Effective" for Athletic performance, Physical performance.

Beta-alanine is possibly effective for athletic and physical performance. Caffeine is likely effective for mental alertness and athletic performance, and it's established as effective for neonatal apnea (a medical use outside this product's scope).

Rhodiola root extract's effectiveness for athletic performance is not established in our data—the evidence we hold rates it insufficient to judge. We don't have effectiveness data on file for citrulline malate or L-dihydroxyphenylalanine in this product.

The evidence, ingredient by ingredient Beta-alanine Caffeine Rhodiola

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Beta-alanine is generally well tolerated but commonly causes a harmless tingling sensation (paresthesia) on the skin and scalp starting about 20 minutes after you take it and lasting roughly an hour; this is dose-dependent and mild at lower amounts. Caffeine in moderate doses is generally safe for healthy adults, though high doses can cause serious side effects.

The most common side effects are anxiety, jitteriness, insomnia, headache, nausea, tremors, and restlessness. Rhodiola is generally well tolerated for short-term use, but long-term safety is not well studied; dizziness and dry mouth or excess saliva are possible.

Beta-alanine, rhodiola, and caffeine all lack sufficient safety data in pregnancy and breastfeeding—the safety information advises against use in both, so talk with your doctor or pharmacist if you're pregnant, trying to become pregnant, or nursing.

Side effects, ingredient by ingredient Beta-alanine Caffeine Rhodiola

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?
  • 2 of the 3 matched ingredients can interact with medications — Rhodiola, Caffeine.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; lithium.
  • For scale: 1,453 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.

Check with your pharmacist before using this product if you take ephedrine (Major interaction risk), blood pressure medications, diabetes drugs, immunosuppressants, certain antibiotics (quinolones), stomach acid reducers (cimetidine), barbiturate sedatives, carbamazepine (an anticonvulsant), clozapine (an antipsychotic), dipyridamole, or any drug metabolized by the liver enzyme systems CYP2C9, P-glycoprotein, CYP1A2, or CYP3A4.

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 pre-workout is built around caffeine and beta-alanine to support exercise performance. It's not for you if you take ephedrine, blood pressure or blood sugar medications, sedatives, anticonvulsants, clozapine, or certain antibiotics without checking first.

Anyone on multiple medications, pregnant, breastfeeding, or with heart or blood pressure concerns should talk to their pharmacist before starting.

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

Assessment coverage: 3 of 5 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 20, 2024.

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 Pre-Workout Tropical Candy, straight from the product label.

Brand Outwork Nutrition
Barcode (UPC) 850017595019
Net contents 226 Gram(s); 0.49 Pound(s)
Market status On market
Date entered into DSLD Jun 20, 2024
DSLD ID 305215
Product type Other Combinations
Supplement form Powder
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 Pre-Workout Tropical Candy by Outwork 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:
5.65 Gram(s)
Maximum serving Sizes:
11.3 Gram(s)
Servings per container
20
UPC/BARCODE
850017595019
IngredientAmount% DV
CarnoSyn3200 mg--
Caffeine Anhydrous300 mg--
Citrulline Malate6000 mg--
Rhodiola root extract300 mg--
L-Dihydroxyphenylalanine150 mg--

Other ingredients: Natural and Artificial flavors, Citric Acid, Silicon Dioxide, Calcium Silicate, Sucralose, Malic Acid, Acesulfame Potassium

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.
Precautions

Supplement product warning Do not use if pregnant, nursing, or under the age of 18.

Do not use if pregnant, nursing, or under the age of 18.

This product is only intended to be consumed by healthy individuals.

Do not consume this product if you have a medical condition or are taking any medications.

Do not exceed recommended serving. Consult with your physician before starting any dietary supplement or exercise program.

Keep out of reach of children.

This product contains caffeine. May not be appropriate for caffeine sensitive individuals. Do not consume with any other stimulants. Assess your tolerance by taking half serving (1 scoop) and, if well tolerated, gradually increase to full serving (2 scoops).

Do not eat freshness packet; keep in bottle.

Manufactured in a facility that also processes milk, soy, peanut, shellfish and wheat products.

Storage

Store in a cool, dry place.

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.

Brand IP Statement(s)

CarnoSyn Carnosine Synthesizer Natural Alternatives International (NAI) is the owner of patents as listed on www.carnosyn.com and registered trademark CarnoSyn.

Formula

Tropical Candy naturally & artificially flavored 6 g Citrulline 3.2 g Beta-Alanine 300 mg Caffeine

Research based ingredients 6 g Citrulline 3.2 g Beta-Alanine 300 mg Caffeine

FDA Statement of Identity

Dietary Supplement

Formulation

Supports energy, focus, stamina, and pump

General Statements

Outwork Nutrition isn't about hype. We don't need it. Our focus is on what we do best: delivering science-based supplements that are effective so you can train harder, recover better, and improve faster. Leave the gimmicks and marketing hype to everyone else, leave the science to us.

@Outworknutritionofficial

Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement, mix two (2) scoops with 8-12 oz of water. New users should assess tolerance with one (1) scoop. Consume 30 minutes before training.

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

See for yourself

Pre-Workout Tropical Candy by Outwork Nutrition label

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

Pre-Workout Tropical Candy 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 Pre-Workout Tropical Candy by Outwork Nutrition

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size5.65 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.

CarnoSyn

No known
interactions
3200 mg per serving Form: 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-int...

CarnoSyn monograph & interactions

Caffeine Anhydrous

Interacts with
655 drugs
300 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

Citrulline Malate

6000 mg per serving

Rhodiola root extract

Interacts with
1,271 drugs
300 mg per serving

Rhodiola is an herb traditionally used to fight fatigue and help the body cope with stress. Some small studies suggest it may modestly reduce fatigue...

Rhodiola root extract monograph & interactions

L-Dihydroxyphenylalanine

150 mg per serving Form: Mucuna pruriens

Other (inactive) ingredients: Natural and Artificial flavors, Citric Acid, Silicon Dioxide, Calcium Silicate, Sucralose, Malic Acid, Acesulfame Potassium. These complete the product’s ingredient list but are not active constituents.

Interaction report

Pre-Workout Tropical Candy by Outwork Nutrition Drug Interactions

Want to check YOUR meds against Pre-Workout Tropical Candy?

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
1,452Drugs
8 Major 947 Moderate 497 Minor

Ingredients driving the most interactions

Rhodiola root extract 1,271
Caffeine Anhydrous 655

Individual Drug Interactions

The ingredients in Pre-Workout Tropical Candy interact with 1,452 drugs. Click any drug to see the details.

2 of the 5 ingredients in Pre-Workout Tropical Candy interact with drugs. Each result below shows which ingredient is responsible. Rhodiola root extract Caffeine Anhydrous

Each ingredient & the kinds of drugs it affects

For each ingredient in Pre-Workout Tropical Candy 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.

Rhodiola root extract10 drug types · 1,271 drugs

Antidiabetes Drugs

Theoretically, taking rhodiola with antidiabetes drugs might increase the risk of hypoglycemia.
In vitro and animal research shows that rhodiola extract can decrease blood glucose due to alpha-glucosidase activity.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, taking rhodiola with antihypertensive drugs might increase the risk of hypotension.
In vitro and animal research shows that rhodiola extract inhibits angiotensin-converting enzyme (ACE) and might lower blood pressure.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, rhodiola might increase levels of drugs metabolized by CYP2C9.
In vitro research shows that rhodiola inhibits CYP2C9. This effect is highly variable and appears to be dependent on the rhodiola product studied. Also, a clinical study in healthy young males found that taking rhodiola extract 290 mg daily for 14 days reduces the metabolism of losartan, a CYP2C9 substrate, by 21% after 4 hours.

Likelihood Possible Evidence B
Immunosuppressants

Theoretically, rhodiola use might interfere with immunosuppressive therapy.
In vitro and animal research show that rhodiola has immunostimulatory effects.

Likelihood Possible Evidence D
Losartan (Cozaar)

Rhodiola might increase the levels and adverse effects of losartan.
A clinical study in healthy young males found that taking rhodiola extract 290 mg daily for 14 days reduces the metabolism of losartan, a CYP2C9 substrate, by 21% after 4 hours.

Likelihood Probable Evidence B
P-Glycoprotein Substrates

Theoretically, rhodiola might increase levels of P-glycoprotein substrates.
In vitro research shows that rhodiola inhibits P-glycoprotein. Theoretically, using rhodiola with P-glycoprotein substrates might increase drug levels and potentially increase the risk of adverse effects.

Likelihood Possible Evidence D
Antidepressant Drugs

Theoretically, rhodiola might increase the risk of adverse effects when taken with antidepressants.
A review of adverse event reports in Poland identified cases of tachyarrhythmias, myalgia, arthralgia, gum pain, restless leg syndrome, swallowing disorders, and changes in consciousness when rhodiola was taken in combination with paroxetine, escitalopram, fluoxetine, sertraline, trazodone, and/or duloxetine.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, rhodiola might increase the risk of adverse effects when taken with CNS depressants.
A review of adverse event reports in Poland identified cases of excessive sedation, myoclonus, hypotension, and hallucinations when rhodiola was taken with haloperidol, diazepam, or alprazolam.

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

Theoretically, rhodiola might increase levels of drugs metabolized by CYP1A2.
In vitro research shows that rhodiola inhibits CYP1A2. This effect is highly variable and appears to be dependent on the rhodiola product studied. However, a clinical study in healthy young males found that taking rhodiola extract 290 mg daily for 14 days does not inhibit the metabolism of caffeine, a CYP1A2 substrate.

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

Theoretically, rhodiola might increase levels of drugs metabolized by CYP3A4.
In vitro research shows that rhodiola inhibits CYP3A4. This effect is highly variable and appears to be dependent on the rhodiola product studied. However, a clinical study in healthy young males found that taking rhodiola extract 290 mg daily for 14 days does not inhibit the metabolism of midazolam, a CYP3A4 substrate.

Likelihood Possible Evidence B
Rhodiola root extract full monograph & 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
The maker

Brand information

Manufacturer and brand details for Pre-Workout Tropical Candy, from the product label.

Outwork Nutrition

See all Outwork Nutrition products
Name
Outwork Nutrition
Street Address
266 Crystal Grove Blvd
City
Lutz
State
FL
ZipCode
33548
Web Address
Outworknutrition.com
Pharmacist Counseling Corner

Pre-Workout Tropical Candy by Outwork Nutrition: Common Questions

Does Pre-Workout Tropical Candy by Outwork Nutrition interact with any medications?
Yes. Based on its ingredients, Pre-Workout Tropical Candy has a known interaction with 1,452 medications, including 8 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Pre-Workout Tropical Candy contains 5 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.
What's the tingling I'll feel if I take this?
That's the beta-alanine causing paresthesia—a harmless pins-and-needles feeling that usually starts on your scalp within 20 minutes and spreads across your body, lasting about an hour. It's dose-dependent, so lower amounts cause milder tingling; at very low doses it might not happen at all.
Can I take this while I'm pregnant or breastfeeding?
The safety information advises against it. Beta-alanine, caffeine, and rhodiola all lack enough data to know they're safe in pregnancy or while nursing. Talk with your doctor or pharmacist about whether this product is right for you.
Will this actually help my workout?
Beta-alanine and caffeine are both possibly to likely effective for athletic performance. Rhodiola's effectiveness for athletic performance isn't established in our data. The other two ingredients (citrulline malate and L-dihydroxyphenylalanine) don't have effectiveness ratings on file for us.
What are the most common side effects?
From caffeine you might get anxiety, insomnia, headache, nausea, tremors, or restlessness. Beta-alanine causes that tingling sensation. Rhodiola may cause dizziness or dry mouth. All are generally well tolerated, but caffeine at high doses can cause serious effects.
How long can I safely take this?
Beta-alanine safety at high doses over the long term hasn't been well studied. Rhodiola is generally well tolerated for short-term use, but long-term safety isn't well established. Your pharmacist can advise on a safe duration for your situation.
Is this safe for kids or teens?
The data doesn't specify a safe age for this product. Caffeine can interfere with sleep and cognitive function in young people, so talk with a pharmacist or doctor before giving this to anyone under 18.

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

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Pre-Workout Tropical Candy label
Go deeper

The Full Monographs Behind Pre-Workout Tropical Candy’s Ingredients

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

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

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

Rhodiola

Interacts with 1,271 drugs

Rhodiola is an herb traditionally used to fight fatigue and help the body cope with stress. Some small studies suggest it may modestly reduce fatigue and improve mood, but the evidence is li...

Read the full Rhodiola monograph →
Sources

Sources & How We Checked

Pre-Workout Tropical Candy'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 262 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.

Beta-alanine 13 references
  1. Harris RC, Tallon MJ, Dunnett M, et al. The absorption of orally supplied beta-alanine and its effect on muscle carnosine synthesis in human vastus lateralis. Amino Acids 2006;30:279-89.
  2. Hill CA, Harris RC, Kim HJ, et al. Influence of beta-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity. Amino Acids 2007;32:225-33.
  3. Bellinger PM, Minahan CL. The effect of ß-alanine supplementation on cycling time trials of different length. Eur J Sport Sci 2016;16(7):829-36.
  4. Chung W, Shaw G, Anderson ME, et al. Effect of 10 week beta-alanine supplementation on competition and training performance in elite swimmers. Nutrients 2012;4(10):1441-53. PubMed
  5. Glenn JM, Gray M, Stewart R, et al. Incremental effects of 28 days of beta-alanine supplementation on high-intensity cycling performance and blood lactate in masters female cyclists. Amino Acids 2015;47(12):2593-600. PubMed
  6. Gross M, Bieri K, Hoppeler H, Norman B, Vogt M. Beta-alanine supplementation improves jumping power and affects severe-intensity performance in professional alpine skiers. Int J Sport Nutr Exerc Metab 2014;24(6):665-73. PubMed
  7. Howe ST, Bellinger PM, Driller MW, Shing CM, Fell JW. The effect of beta-alanine supplementation on isokinetic force and cycling performance in highly trained cyclists. Int J Sport Nutr Exerc Metab 2013;23(6):562-70. PubMed
  8. Sweeney KM, Wright GA, Glenn Brice A, Doberstein ST. The effect of beta-alanine supplementation on power performance during repeated sprint activity. J Strength Cond Res 2010;24(1):79-87.
  9. Décombaz J, Beaumont M, Vuichoud J, Bouisset F, Stellingwerff T. Effect of slow-release ß-alanine tablets on absorption kinetics and paresthesia. Amino Acids 2012;43(1):67-76. Erratum in: Amino Acids 2013;45(4):1015.
  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

See these in context on the Beta-alanine monograph →

Caffeine 236 references
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  11. Thu OK, Nilsen OG, Hellum B. In vitro inhibition of cytochrome P-450 activities and quantification of constituents in a selection of commercial Rhodiola rosea products. Pharm Bio. 2016 Dec;54(12):3249-3256.
  12. Thu OK, Spigset O, Nilsen OG, Hellum B. Effect of commercial Rhodiola rosea on CYP enzyme activity in humans. Eur J Clin Pharmacol. 2016 Mar;72(3):295-300. PubMed
  13. Woron J, Siwek M. Unwanted effects of psychotropic drug interactions with medicinal products and diet supplements containing plant extracts. Psychiatr Pol 2018;52(6):983-96. PubMed

See these in context on the Rhodiola monograph →

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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