Interactions on record — worth a quick check against your medications. Based on 8 of 20 ingredients. Check your meds →
Dietary supplement

Advanced Therapeutics SynaptaLean Rx-Fat Loss Ingredients & Drug Interactions

by NaturesPlus

Advanced Therapeutics SynaptaLean Rx-Fat Loss label
See full label image
Tablet Or Pill Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Advanced Therapeutics SynaptaLean Rx-Fat Loss 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: Moderate

Advanced Therapeutics SynaptaLean Rx-Fat Loss is a dietary supplement by NaturesPlus with 20 active ingredients. Its ingredients are commonly taken for preventing or treating thiamine deficiency, beriberi, wernicke-korsakoff syndrome (alcohol-related).Based on those ingredients, 1,385 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are RhodiGen, Passion Flower extract, 5-HTP. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Advanced Therapeutics SynaptaLean Rx-Fat Loss by NaturesPlus

Ask about any prescription or over-the-counter medication and we check it for interactions with Advanced Therapeutics SynaptaLean Rx-Fat Loss by NaturesPlus — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Advanced Therapeutics SynaptaLean Rx-Fat Loss by NaturesPlus

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

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 3 of its 20 active ingredients.
  • “SynaptaLean Neuronutrient Complex” is a proprietary blend — the label gives one combined amount (3,771 mg) without saying how much of each component you get.
  • “Full Spectrum Whole Food Blend” is a proprietary blend — the label gives one combined amount (99 mg) without saying how much of each component you get.

This product contains 20 ingredients, including ten active ones we can identify: thiamine and thiamine hydrochloride (B vitamins for energy metabolism), chromium and ChromeMate (mineral for blood sugar support), three forms of vitamin B6 (pyridoxine hydrochloride, pyridoxal 5-phosphate, and vitamin B6 itself—for nerve and mood function), 5-HTP (a serotonin precursor for mood), L-tyrosine (an amino acid for focus), L-glutamine (an amino acid for muscle and gut), passion flower extract (for relaxation), and rhodiola (RhodiGen, an herbal adaptogen for stress). The product also contains proprietary blends labeled SynaptaLean Neuronutrient Complex, Synaptose, D-PhenEze, Red Whole Food Blend, Full Spectrum Whole Food Blend, and green, white, yellow, and blue whole food blends—whose individual ingredients aren't fully detailed here.

Inactive ingredients include microcrystalline cellulose, magnesium stearate, cellulose, stearic acid, silica, hydroxypropyl methylcellulose, and pharmaceutical glaze.

Does it work?

Not established
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
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: weight management and reduced cravings.
  • We looked for evidence on: Binge eating disorder, appetite suppression, metabolic support, satiety.
  • The closest evidence on file: Chromium is rated "Insufficient Reliable Evidence To Rate" for Binge eating disorder (Natural Medicines).

The evidence for this product's ingredients is mixed. Thiamine is effective for thiamine deficiency and Wernicke-Korsakoff syndrome (a serious brain condition from severe deficiency), and possibly effective for menstrual pain.

Chromium is likely effective for chromium deficiency and possibly effective for diabetes control. Vitamin B6 is effective for certain types of anemia, B6 deficiency, and a rare seizure condition, and possibly effective for pregnancy-related nausea.

5-HTP is possibly effective for depression, though the data we hold are limited. L-tyrosine is effective for PKU (a rare inherited disorder) and possibly effective for thinking and memory, though not for athletic performance.

L-glutamine is effective for sickle cell disease and possibly effective for recovery after surgery or serious illness. Passion flower is possibly effective for insomnia and anxiety before medical procedures.

Rhodiola's evidence is insufficient to rate—we don't have reliable data showing it works for the conditions commonly claimed. For the proprietary blends and other components (Synaptose, D-PhenEze, metallosaccharide complex, and the colored whole food blends), effectiveness data aren't available to us.

The evidence, ingredient by ingredient Thiamine Chromium Vitamin B6 5-htp Tyrosine Glutamine Passion Flower 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 8 of the 8 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 8 of 8.
  • General safety write-ups exist for 8 of 8.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most of these ingredients are generally well tolerated at typical supplement doses. Thiamine is very safe taken by mouth in normal amounts and is likely safe in pregnancy and lactation when used as directed by your provider.

Chromium is usually well tolerated but at high or long-term doses may pose risks; avoid extra supplement doses in pregnancy unless your doctor advises otherwise. Vitamin B6 is safe at normal dietary amounts and standard supplement doses, but high doses over time—especially above 1,000 mg daily or total intakes of 1,000 grams or more—can damage nerves (a condition called sensory neuropathy).

Some trial data also associate high B6 intake in women with increased rectal cancer risk, though a post-hoc analysis of stroke patients taking B6 with folic acid and B12 did not show overall cancer risk. 5-HTP commonly causes nausea, vomiting, diarrhea, headache, drowsiness, and loss of appetite—often dose-dependent.

Rare serious effects include aggression, hallucinations, and mania. Avoid 5-HTP in pregnancy and while breastfeeding due to insufficient safety data.

L-tyrosine is generally well tolerated; adverse effects are uncommon but may include fatigue, headache, heartburn, and nausea. Pregnancy and breastfeeding safety data are insufficient—talk with your provider.

L-glutamine is usually well tolerated but can cause bloating, gas, constipation, nausea, vomiting, and headache; avoid supplemental doses in pregnancy and lactation unless recommended by your doctor. Passion flower is well tolerated short-term but causes drowsiness and confusion in some people; avoid it in pregnancy (possibly unsafe) and while breastfeeding due to lack of safety data.

Rhodiola seems well tolerated for short-term use and may cause dizziness, dry mouth, or excessive saliva; long-term safety is unknown, and avoid it in pregnancy and lactation.

Side effects, ingredient by ingredient Thiamine Chromium Vitamin B6 5-htp Tyrosine Glutamine Passion Flower Rhodiola

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 8 of the 8 matched ingredients can interact with medications — 5-htp, Passion Flower, Glutamine, Rhodiola, Chromium, among others.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: seizure medications; immunosuppressants / transplant drugs; diabetes medications; Parkinson's medications.
  • For scale: 1,386 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.

Moderate-severity interactions are documented with seizure medications (phenobarbital, phenytoin), blood sugar medications (insulin and antidiabetes drugs), thyroid hormone (levothyroxine), blood pressure medications, antidepressants and serotonergic drugs, amiodarone, levodopa, immunosuppressants, losartan, and sedating medications. Minor interactions occur with trimethoprim, NSAIDs, aspirin, and drugs processed through liver enzymes CYP1A2, CYP2C9, CYP3A4, OATP transporters, and P-glycoprotein.

Several ingredients could not be checked for interactions. Check all your medications against this product using the tool below.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

This is a multi-ingredient supplement aimed at weight loss and focus. If you take any prescription medications—especially for blood sugar, blood pressure, seizures, depression, thyroid function, Parkinson's disease, or sedation—talk to your pharmacist before adding this product.

The vitamin B6 content and multiple interactive herbs make it important to check your exact medications first. Pregnant or breastfeeding people should discuss this with their doctor, as several ingredients carry safety cautions or insufficient data.

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

Assessment coverage: 12 of 20 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Oct 24, 2023.

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 Advanced Therapeutics SynaptaLean Rx-Fat Loss, straight from the product label.

Brand NaturesPlus
Barcode (UPC) 097467049901
Net contents 60 Tablet(s)
Market status On market
Date entered into DSLD Oct 24, 2023
DSLD ID 298229
Product type Other Combinations
Supplement form Tablet Or Pill
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free
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 Advanced Therapeutics SynaptaLean Rx-Fat Loss by NaturesPlus, 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:
2 Tablet(s), 6 Tablet(s)
Maximum serving Sizes:
2 Tablet(s), 6 Tablet(s)
Servings per container
10
UPC/BARCODE
097467049901
IngredientAmount% DV
Thiamine30 mg, 10 mg2500%, 833%
Chromium399 mcg, 133 mcg1140%, 380%
Pyridoxine Hydrochloride0 NP, 0 NP--
5-HTP0 NP, 0 NP--
Pyridoxal 5-Phosphate0 NP, 0 NP--
L-Tyrosine0 NP, 0 NP--
L-Glutamine0 NP, 0 NP--
Vitamin B621 mg, 7 mg1235%, 412%
Thiamine Hydrochloride0 NP, 0 NP--
Red Whole Food Blend0 NP, 0 NP--
SynaptaLean Neuronutrient Complex3771 mg, 1257 mg--
Synaptose0 NP, 0 NP--
D-PhenEze0 NP, 0 NP--
Passion Flower extract0 NP, 0 NP--
Metallosaccharide Complex0 NP, 0 NP--
RhodiGen0 NP, 0 NP--
ChromeMate0 NP, 0 NP--
Full Spectrum Whole Food Blend99 mg, 33 mg--
Green Whole Food Blend0 NP, 0 NP--
White Whole Food Blend0 NP, 0 NP--
Yellow Whole Food Blend0 NP, 0 NP--
Blue Whole Food Blend0 NP, 0 NP--

Other ingredients: Microcrystalline Cellulose, Magnesium Stearate, Cellulose, Stearic Acid, Silica, Hydroxypropyl Methylcellulose, Pharmaceutical Glaze

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

Directions: as a dietary supplement for adults: to nutritionally support healthy weight management, take 2 tablets daily. For clinical strength activity, promoting reduced cravings and successful and sustainable fat loss, take 6 tablets daily. For best results, take with juice or water and not with high-protein foods.

Storage

Keep tightly closed in a cool, dry place.

Precautions

Keep out of reach of children.

Phenylketonurics - contains phenylalanine, but not as a synthetic sweetener.

Schizophrenics - consult a doctor before taking a dopamine agonist.

Contains crustacean.

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.

Formulation

This is not a prescription product. It is a dietary supplement made with the highest possible quality standards.

Successful, sustainable fat loss

Appetite & craving control

Gluten free

Nutritional support for Successful and sustainable fat loss Healthy brain function

Brand IP Statement(s)

Synatose (a complex of patented Synaptamine and Zehntose) is a trademark of Allied Nutraceutical ingredients, LLC. Synaptamine is a registered trademark of Synaptamine, Inc. and protected by US and EU patents. Zehntose is a trademark of Cetra Nutraceuticals, Inc. D-PhenEze Metallosacchride and RhodiGen are trademarks of Allied Nutraceutical Ingredients, LLC. ChromeMate is a registered trademark of InterHealth NI.

Copyright Natural Organics

FDA Statement of Identity

Dietary Supplement

General Statements

Servings Per Container 30 or 10

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

See for yourself

Advanced Therapeutics SynaptaLean Rx-Fat Loss by NaturesPlus label

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

Advanced Therapeutics SynaptaLean Rx-Fat Loss 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 Advanced Therapeutics SynaptaLean Rx-Fat Loss by NaturesPlus

These are the 20 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Tablet(s) Dosage formTablet Or Pill Servings per container10 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.

Thiamine

Interacts with
3 drugs
30 mg per serving Form: Thiamine Hydrochloride

Thiamine (vitamin B1) is an essential nutrient your body needs to turn food into energy and to keep your nerves and heart healthy. Most people get eno...

Thiamine monograph & interactions

Chromium

Interacts with
178 drugs
399 mcg per serving Form: Chromium Polynicotinate

Chromium is an essential trace mineral involved in how the body handles sugar and fat. Some studies suggest it may modestly help blood sugar control i...

Chromium monograph & interactions

Vitamin B6

Interacts with
210 drugs
21 mg per serving Form: Pyridoxal 5-Phosphate, Pyridoxine Hydrochloride

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is b...

Vitamin B6 monograph & interactions

SynaptaLean Neuronutrient Complex

3771 mg per serving

Full Spectrum Whole Food Blend

99 mg per serving
  • › Red Whole Food Blend
  • › Green Whole Food Blend
  • › White Whole Food Blend
  • › Yellow Whole Food Blend
  • › Blue Whole Food Blend

Other (inactive) ingredients: Microcrystalline Cellulose, Magnesium Stearate, Cellulose, Stearic Acid, Silica, Hydroxypropyl Methylcellulose, Pharmaceutical Glaze. These complete the product’s ingredient list but are not active constituents.

Interaction report

Advanced Therapeutics SynaptaLean Rx-Fat Loss by NaturesPlus Drug Interactions

Want to check YOUR meds against Advanced Therapeutics SynaptaLean Rx-Fat Loss?

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
1,385Drugs
1,014 Moderate 371 Minor

Ingredients driving the most interactions

RhodiGen 1,271
Passion Flower extract 836
5-HTP 398
Vitamin B6 210
Chromium 178

Individual Drug Interactions

The ingredients in Advanced Therapeutics SynaptaLean Rx-Fat Loss interact with 1,385 drugs. Click any drug to see the details.

8 of the 20 ingredients in Advanced Therapeutics SynaptaLean Rx-Fat Loss interact with drugs. Each result below shows which ingredient is responsible. RhodiGen Passion Flower extract 5-HTP Vitamin B6 Chromium L-Glutamine L-Tyrosine Thiamine

Each ingredient & the kinds of drugs it affects

For each ingredient in Advanced Therapeutics SynaptaLean Rx-Fat Loss 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.

RhodiGen10 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
RhodiGen full monograph & interactions

Passion Flower extract3 drug types · 836 drugs

Cns Depressants

Concomitant use of passion flower with sedative drugs might cause additive effects and side effects.
Research in animals and humans shows that passion flower has sedative effects which can be additive when used with sedative medications like lorazepam.

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

Theoretically, passion flower might decrease the effects of CYP3A4 substrates.
In vitro research suggests that passion flower can induce CYP3A4 enzymes, albeit to a much lower degree than rifampin, a known CYP3A4 inducer.

Likelihood Possible Evidence D
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Theoretically, passion flower might reduce the bioavailability of OATP2B1 and OATP1A2 substrates.
In vitro research shows that the passion flower constituents apigenin and vitexin inhibit OATP2B1 and OATP1A2. This inhibition may be dose-dependent. One specific high-flavonoid passion flower extract (Valverde) seems to inhibit OATP2B1 and OATP1A2, while another extract with a lower flavonoid concentration (Arkocaps) shows less potent inhibition. OATPs are responsible for the uptake of drugs and other compounds into the body; however, the specific activities of OATP2B1 and OATP1A2 are not well characterized.

Likelihood Possible Evidence D
Passion Flower extract full monograph & interactions

5-HTP3 drug types · 398 drugs

Carbidopa (Lodosyn)

Combining 5-HTP and carbidopa can increase the risk of serotonergic side effects.
Carbidopa is sometimes used with 5-HTP to minimize peripheral 5-HTP metabolism and boost the amount that reaches the brain. However, this combination might also increase the risk of some side effects including hypomania, restlessness, rapid speech, anxiety, insomnia, and aggressiveness. Combining carbidopa and 5-HTP might also increase the risk of scleroderma-like skin changes due to elevated serotonin levels.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, concomitant use of 5-HTP with medications that cause sedation might have additive effects.
In clinical trials, 5-HTP has been associated with drowsiness and somnolence.

Likelihood Possible Evidence D
Serotonergic Drugs

Combining serotonergic drugs with 5-HTP might cause additive serotonergic effects.
5-HTP can increase serotonin levels and cause serotonergic effects. Theoretically, combining serotonergic drugs with 5-HTP might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders. However, serotonin syndrome with 5-HTP has not yet been reported in humans. Monitor patients for signs of serotonin syndrome and other serotonergic side effects if using 5-HTP with serotonergic drugs.

Likelihood Possible Evidence D
5-HTP full monograph & interactions

Vitamin B65 drug types · 210 drugs

Amiodarone (Cordarone)

Theoretically, vitamin B6 might increase the photosensitivity caused by amiodarone.
Despite initial case reports suggesting that pyridoxine may have a protective effect against amiodarone-induced photosensitivity, preliminary clinical research suggests that pyridoxine may actually exacerbate this adverse effect.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, vitamin B6 may have additive effects when used with antihypertensive drugs.
Research in hypertensive rats shows that vitamin B6 can decrease systolic blood pressure. Similarly, clinical research in patients with hypertension shows that taking high doses of vitamin B6 may reduce systolic and diastolic blood pressure, possibly by reducing plasma levels of epinephrine and norepinephrine.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

High doses of vitamin B6 may reduce the levels and clinical effects of phenobarbital.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenobarbital, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenobarbital to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

High doses of vitamin B6 may reduce the levels and clinical effects of phenytoin.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenytoin, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenytoin to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Levodopa

Vitamin B6 may increase the metabolism of levodopa when taken alone, but not when taken in conjunction with carbidopa.
Vitamin B6 (pyridoxine) enhances the metabolism of levodopa, reducing its clinical effects. However, this interaction does not occur when carbidopa is used concurrently with levodopa (Sinemet). Therefore, it is not likely to be a problem in most people.

Likelihood Unlikely Evidence D
Vitamin B6 full monograph & interactions

Chromium5 drug types · 178 drugs

Antidiabetes Drugs

Theoretically, chromium may have additive effects with antidiabetic agents and increase the risk of hypoglycemia.
Some research shows that taking chromium might lower blood glucose levels, especially in patients with poorly controlled type 2 diabetes.

Likelihood Possible Evidence A
Insulin

Theoretically, concomitant use of chromium and insulin might increase the risk of hypoglycemia.
In clinical research, chromium has been shown to increase insulin sensitivity,

Likelihood Possible Evidence B
Levothyroxine (Synthroid, Others)

Chromium might bind levothyroxine in the intestinal tract and decrease levothyroxine absorption.
Clinical research in healthy volunteers shows that taking chromium picolinate 1000 mcg with levothyroxine 1 mg decreases serum levels of levothyroxine by 17% when compared to taking levothyroxine alone. Advise patients to take levothyroxine at least 30 minutes before or 3-4 hours after taking chromium.

Likelihood Probable Evidence B
Aspirin

Theoretically, aspirin might increase chromium absorption.
Animal research suggests that aspirin may increase chromium absorption and chromium levels in the blood.

Likelihood Possible Evidence D
Nonsteroidal Anti-Inflammatory Drugs (Nsaids)

NSAIDs might increase chromium levels in the body.
Drugs that are prostaglandin inhibitors, such as NSAIDs, seem to increase chromium absorption and retention.

Likelihood Possible Evidence D
Chromium full monograph & interactions

L-Glutamine1 drug type · 50 drugs

Anticonvulsants

Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Glutamine is metabolized to the excitatory neurotransmitter glutamate. Glutamate might have antagonistic effects with anticonvulsant drugs. However, this interaction has not yet been reported in humans.

Likelihood Possible Evidence D
L-Glutamine 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

Thiamine1 drug type · 3 drugs

Trimethoprim (Proloprim)

Trimethoprim might increase blood levels of thiamine.
In vitro, animal, and clinical research suggest that trimethoprim inhibits intestinal thiamine transporter ThTR-2, hepatic transporter OCT1, and renal transporters OCT2, MATE1, and MATE2, resulting in paradoxically increased thiamine plasma concentrations.

Likelihood Probable Evidence B
Thiamine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Advanced Therapeutics SynaptaLean Rx-Fat Loss, from the product label.

NaturesPlus

See all NaturesPlus products
Name
Natural Organics Laboratories Inc. makers of Nature's Plus
Street Address
9500 New Horizons Blvd.
City
Amityville
State
NY
ZipCode
11701
Web Address
www.naturesplus.com
Pharmacist Counseling Corner

Advanced Therapeutics SynaptaLean Rx-Fat Loss by NaturesPlus: Common Questions

Does Advanced Therapeutics SynaptaLean Rx-Fat Loss by NaturesPlus interact with any medications?
Yes. Based on its ingredients, Advanced Therapeutics SynaptaLean Rx-Fat Loss has a known interaction with 1,385 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Advanced Therapeutics SynaptaLean Rx-Fat Loss contains 20 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.
Can I take this if I'm on blood pressure medicine?
No, not without talking to your pharmacist first. Both vitamin B6 and rhodiola may lower blood pressure further, and rhodiola also interacts with some medications that process through the liver. Your pharmacist can check your specific medicine.
Will this affect my thyroid medication?
Yes, possibly. Chromium in this product may bind to levothyroxine and reduce how much your body absorbs, lowering its effectiveness. If you take thyroid medication, we'd recommend spacing out doses and checking with your pharmacist.
Is this safe to take if I have diabetes or prediabetes?
Not without medical guidance. Chromium and rhodiola may both lower blood sugar, and if you're already on insulin or diabetes medication, that could raise your low blood sugar risk. Talk to your doctor or pharmacist first.
Can I take this while pregnant or breastfeeding?
Several ingredients don't have enough safety data in pregnancy or lactation—5-HTP, passion flower, and rhodiola should be avoided. Thiamine and chromium are likely safe in pregnancy at small dietary amounts, but supplemental doses need guidance from your provider. Talk with your doctor before taking this product if you're pregnant or nursing.
What's the most common side effect I should expect?
Nausea, diarrhea, headache, and dizziness are among the most common effects reported with the active ingredients, especially 5-HTP and chromium. These are often dose-dependent—lower doses may mean fewer problems. If you experience them, let us know.
Does this actually help with weight loss?
The evidence isn't established for most of these ingredients in our data. Chromium is possibly effective for diabetes control, which might support weight management in some people, but the product as a whole hasn't been tested for fat loss in the research we hold. Talk to your pharmacist about realistic expectations.

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.

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Go deeper

The Full Monographs Behind Advanced Therapeutics SynaptaLean Rx-Fat Loss’s Ingredients

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

Herb & supplement monograph

Thiamine

Interacts with 3 drugs

Thiamine (vitamin B1) is an essential nutrient your body needs to turn food into energy and to keep your nerves and heart healthy. Most people get enough from food, but supplements are clear...

Read the full Thiamine monograph → Herb & supplement monograph

Chromium

Interacts with 178 drugs

Chromium is an essential trace mineral involved in how the body handles sugar and fat. Some studies suggest it may modestly help blood sugar control in certain people with type 2 diabetes, b...

Read the full Chromium monograph → Herb & supplement monograph

Vitamin B6

Interacts with 210 drugs

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is best known for helping with pregnancy-rel...

Read the full Vitamin B6 monograph → Herb & supplement monograph

5-htp

Interacts with 398 drugs

5-HTP is a compound your body uses to make serotonin, and people take it as a supplement hoping to improve mood, sleep, and headaches. Some early research is promising, but the overall evide...

Read the full 5-htp 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

Glutamine

Interacts with 50 drugs

Glutamine is the most abundant amino acid in the body and is usually made in your muscles. A prescription form is FDA-approved to help reduce sickle cell disease complications, but for most...

Read the full Glutamine monograph → Herb & supplement monograph

Passion Flower

Interacts with 836 drugs

Passion flower is a traditional calming herb that many people use for anxiety and sleep. Early studies hint it may help with mild anxiety and restlessness, but the evidence is limited and mo...

Read the full Passion Flower 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

Advanced Therapeutics SynaptaLean Rx-Fat Loss'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 171 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.

Thiamine 7 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  3. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
  4. Rogovik, A. L., Vohra, S., and Goldman, R. D. Safety considerations and potential interactions of vitamins: should vitamins be considered drugs? Ann.Pharmacother. 2010;44(2):311-324. PubMed
  5. Arruti N, Bernedo N, Audicana MT, Villarreal O, Uriel O, Muñoz D. Systemic allergic dermatitis caused by thiamine after iontophoresis. Contact Dermatitis. 2013 Dec;69(6):375-6. PubMed
  6. Thiamine hydrochloride injection package insert. Lake Zurich, IL: Fresenius Kabi, LLC; September 2019.
  7. Vora B, Wen A, Yee SW, et al. The Effect of Trimethoprim on Thiamine Absorption: A Transporter-Mediated Drug-Nutrient Interaction. Clin Pharmacol Ther 2023;114(2):381-392.

See these in context on the Thiamine monograph →

Chromium 53 references
  1. Cerulli J, Grabe DW, Gauthier I, et al. Chromium picolinate toxicity. Ann Pharmacother 1998;32:428-31. PubMed
  2. Urberg M, Zemel MB. Evidence for synergism between chromium and nicotinic acid in the control of glucose tolerance in elderly humans. Metabolism 1987;36:896-9. PubMed
  3. Mohamedshah FY, Moser-Veillon PB, Yamini S, et al. Distribution of a stable isotope of chromium (53Cr) in serum, urine, and breast milk in lactating women. Am J Clin Nutr 1998;67:1250-5. PubMed
  4. Wasser WG, Feldman NS, D'Agati VD. Chronic renal failure after ingestion of over-the-counter chromium picolinate. [letter]. Ann Intern Med 1997;126:410. PubMed
  5. Mertz W. Interaction of chromium with insulin: a progress report. Nutr Rev 1998;56:174-7. PubMed
  6. Anderson RA. Chromium, glucose intolerance and diabetes. J Am Coll Nutr 1998;17:548-55. PubMed
  7. McLeod MN, Gaynes BN, Golden RN. Chromium potentiation of antidepressant pharmacotherapy for dysthymic disorder in 5 patients. J Clin Psych 1999;60:237-40. PubMed
  8. Fowler JF Jr. Systemic contact dermatitis caused by oral chromium picolinate. Cutis 2000;65:116. DOI
  9. Trent LK, Thieding-Cancel D. Effects of chromium picolinate on body composition. J Sports Med Phys Fitness 1995;35:273-80.
  10. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
  11. Rabinovitz H, Friedensohn A, Leibovitz A, et al. Effect of chromium supplementation on blood glucose and lipid levels in type 2 diabetes mellitus elderly patients. Int J Vitam Nutr Res 2004;74:178-82. PubMed
  12. Lanca S, Alves A, Vieira AI, et al. Chromium-induced toxic hepatitis. Eur J Intern Med 2002;13:518-20. PubMed
  13. Kockler DR, McCarthy MW, Lawson CL. Seizure activity and unresponsiveness after hydroxycut ingestion. Pharmacotherapy 2001;21:647-51.. PubMed
  14. Davidson JR, Abraham K, Connor KM, McLeod MN. Effectiveness of chromium in atypical depression: a placebo-controlled trial. Biol Psychiatry 2003;53:261-4.. PubMed
  15. Food Standards Agency. Medicines and Healthcare products Regulatory Agency (MHRA). Expert Group on Vitamins and Minerals. Available at: http://cot.food.gov.uk/sites/default/files/vitmin2003.pdf.
  16. Mouser JF, Hak EB, Helms RA, et al. Chromium and zinc concentrations in pediatric patients receiving long-term parenteral nutrition. Am J Health Syst Pharm 1999;56:1950-6. PubMed
  17. Stevens T, Qadri A, Zein NN. Two patients with acute liver injury associated with use of the herbal weight-loss supplement hydroxycut. Ann Intern Med 2005;142:477-8. PubMed
  18. Wani S, Weskamp C, Marple J, Spry L. Acute tubular necrosis associated with chromium picolinate-containing dietary supplement. Ann Pharmacother 2006;40:563-6. PubMed
  19. Kleefstra N, Houweling ST, Jansman FG, et al. Chromium treatment has no effect in patients with poorly controlled, insulin-treated type 2 diabetes in an obese Western population: a randomized, double-blind, placebo-controlled trial. Diabetes Care 2006;29: PubMed
  20. Martin J, Wang ZQ, Zhang XH, et al. Chromium picolinate supplementation attenuates body weight gain and increases insulin sensitivity in subjects with type 2 diabetes. Diabetes Care 2006;29:1826-32. PubMed
  21. Singer GM, Geohas J. The effect of chromium picolinate and biotin supplementation on glycemic control in poorly controlled patients with type 2 diabetes mellitus: a placebo-controlled, double-blinded, randomized trial. Diabetes Technol Ther 2006;8:636-43. PubMed
  22. John-Kalarickal J, Pearlman G, Carlson HE. New medications which decrease levothyroxine absorption. Thyroid 2007;17:763-5. PubMed
  23. Yazaki Y, Faridi Z, Ma Y, et al. A pilot study of chromium picolinate for weight loss. J Altern Complement Med 2010;16:291-9. PubMed
  24. Davis ML, Seaborn CD, and Stoecker BJ. Effects of over-the-counter drugs on chromium retention and urinary excretion in rats. Nutrition Research 1995;15(2):201-210.
  25. Young P, Turiansky G, Bonner M, and et al. Acute generalized exanthematous pustulosis induced by chromium picolinate. J.Am Acad.Dermatol. 1999;41(5 Pt 2):820-823. PubMed
  26. Gibb, H. J., Lees, P. S., Pinsky, P. F., and Rooney, B. C. Lung cancer among workers in chromium chemical production. Am J Ind.Med 2000;38(2):115-126. DOI
  27. Gibb, H. J., Lees, P. S., Pinsky, P. F., and Rooney, B. C. Clinical findings of irritation among chromium chemical production workers. Am J Ind.Med 2000;38(2):127-131. PubMed
  28. Pittler, M. H. and Ernst, E. Dietary supplements for body-weight reduction: a systematic review. Am.J.Clin Nutr. 2004;79(4):529-536. PubMed
  29. Pei, D., Hsieh, C. H., Hung, Y. J., Li, J. C., Lee, C. H., and Kuo, S. W. The influence of chromium chloride-containing milk to glycemic control of patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled trial. Metabolism 2 PubMed
  30. Hisatomi, K., Ishii, H., Hashiguchi, K., Seki, M., Ide, M., Sugiyama, K., Ishimoto, H., Nakayama, S., Mukae, H., and Kohno, S. Interstitial pneumonia caused by inhalation of fumes of nickel and chrome. Respirology. 2006;11(6):814-817. PubMed
  31. Kleefstra, N., Houweling, S. T., Bakker, S. J., Verhoeven, S., Gans, R. O., Meyboom-de Jong, B., and Bilo, H. J. Chromium treatment has no effect in patients with type 2 diabetes in a Western population: a randomized, double-blind, placebo-controlled tri DOI
  32. Parsons, A., Ingram, J., Inglis, J., Aveyard, P., Johnstone, E., Brown, K., Franklin, M., and Bermudez, I. A proof of concept randomised placebo controlled factorial trial to examine the efficacy of St John's wort for smoking cessation and chromium to pr
  33. Bagdon RE and Hazen RE. Skin permeation and cutaneous hypersensitivity as a basis for making risk assessments of chromium as a soil contaminant. Environ.Health Perspect. 1991;92:111-119. PubMed
  34. Bharmal, S. V., Moyes, V., Ahmed, S., and Grossman, A. Hypoglycaemia: possible mediation by chromium salt medication. Hormones.(Athens.) 2010;9(2):181-183. PubMed
  35. Krol, E., Krejpcio, Z., Byks, H., Bogdanski, P., and Pupek-Musialik, D. Effects of chromium brewer's yeast supplementation on body mass, blood carbohydrates, and lipids and minerals in type 2 diabetic patients. Biol.Trace Elem.Res. 2011;143(2):726-737.
  36. Unisa, S., Jagannath, P., Dhir, V., Khandelwal, C., Sarangi, L., and Roy, T. K. Population-based study to estimate prevalence and determine risk factors of gallbladder diseases in the rural Gangetic basin of North India. HPB (Oxford) 2011;13(2):117-125. PubMed
  37. Noda, S., Asano, Y., and Sato, S. Lichen planus in a patient with long-term exposure to chrome. Eur.J.Dermatol. 2011;21(3):417-418. PubMed
  38. Xiang, J., Sun, Z., and Huan, J. N. Intensive chromic acid burns and acute chromium poisoning with acute renal failure. Chin Med.J.(Engl.) 7-5-2011;124(13):2071-2073.
  39. Chhabra, D., Oda, K., Jagannath, P., Utsunomiya, H., Takekoshi, S., and Nimura, Y. Chronic heavy metal exposure and gallbladder cancer risk in India, a comparative study with Japan. Asian Pac.J.Cancer Prev. 2012;13(1):187-190. PubMed
  40. Huszonek, J. Over-the-counter chromium picolinate. Am J Psychiatry 1993;150(10):1560-1561. PubMed
  41. Bunner S and McGinnis R. Chromium-induced hypoglycemia. Psychosomatics 1998;39(3):298-299. PubMed
  42. Martin, W. R. and Fuller, R. E. Suspected chromium picolinate-induced rhabdomyolysis. Pharmacotherapy 1998;18(4):860-862. DOI
  43. Proctor, D. M., Fredrick, M. M., Scott, P. K., Paustenbach, D. J., and Finley, B. L. The prevalence of chromium allergy in the United States and its implications for setting soil cleanup: a cost-effectiveness case study. Regul.Toxicol Pharmacol 1998;28(1 PubMed
  44. De Marchi S, Cecchin E, De Marchi SU. Systemic allergic dermatitis resulting from oral administration of chromium with a food supplement. Contact Dermatitis 2014;70(2):123-5. PubMed
  45. Hedberg YS, Gumulka M, Lind ML, Matura M, Lidén C. Severe occupational chromium allergy despite cement legislation. Contact Dermatitis. 2014;70(5):321-3. PubMed
  46. Thyssen JP, Jellesen MS, Møller P, Menné T, Johansen JD. Allergic chromium dermatitis from wearing 'chromium-free' footwear. Contact Dermatitis 2014;70(3):185-7. PubMed
  47. Liu Y, Cotillard A, Vatier C, et al. A Dietary Supplement Containing Cinnamon, Chromium and Carnosine Decreases Fasting Plasma Glucose and Increases Lean Mass in Overweight or Obese Pre-Diabetic Subjects: A Randomized, Placebo-Controlled Trial. PLoS One.
  48. Jamilian M, Asemi Z. Chromium Supplementation and the Effects on Metabolic Status in Women with Polycystic Ovary Syndrome: A Randomized, Double-Blind, Placebo-Controlled Trial. Ann Nutr Metab. 2015;67(1):42-8. PubMed
  49. Guimarães MM, Carvalho AC, Silva MS. Effect of chromium supplementation on the glucose homeostasis and anthropometry of type 2 diabetic patients: Double blind, randomized clinical trial: Chromium, glucose homeostasis and anthropometry. J Trace Elem Med Bi PubMed
  50. Paiva AN, Lima JG, Medeiros AC, et al. Beneficial effects of oral chromium picolinate supplementation on glycemic control in patients with type 2 diabetes: A randomized clinical study. J Trace Elem Med Biol. 2015;32:66-72. PubMed
  51. Yin RV, Phung OJ. Effect of chromium supplementation on glycated hemoglobin and fasting plasma glucose in patients with diabetes mellitus. Nutr J. 2015;14:14. PubMed
  52. Jamilian M, Zadeh Modarres S, Amiri Siavashani M, et al. The influences of chromium supplementation on glycemic control, markers of cardio-metabolic risk, and oxidative stress in infertile polycystic ovary syndrome women candidate for in vitro fertilizati
  53. Alinaghi F, Thyssen JP, Zachariae C, Johansen JD. No immediate effect of regulatory reduction of chromium in leather among adult patients with chromium allergy. Contact Dermatitis 2021;85(5):514-522. PubMed

See these in context on the Chromium monograph →

Vitamin B6 32 references
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  2. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  3. Geerling BJ, Dagnelie PC, Badart-Smook A, et al. Diet as a risk factor for the development of ulcerative colitis. Am J Gastroenterol 2000;95:1008-13. PubMed
  4. South M. Neonatal seizures after pyridoxine use -- reply. Lancet 1999;354:2083. PubMed
  5. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
  6. Baxter P, Aicardi J. Neonatal seizures after pyridoxine use. Lancet 1999;354:2082-3. PubMed
  7. Bendich A, Cohen M. Vitamin B6 safety issues. Ann N Y Acad Sci 1990;585:321-30.
  8. Schaumburg H, Kaplan J, Windebank A. Sensory neuropathy from pyridoxine abuse. A new megavitamin syndrome. N Engl J Med 1983;309:445-8. PubMed
  9. Gordon N. Pyridoxine dependency: an update. Dev Med Child Neurol 1997;39:63-5. PubMed
  10. Lewis PJ. Pain in the hand and wrist. Pyridoxine supplements may help patients with carpal tunnel syndrome. BMJ 1995;310:1534. PubMed
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  12. Mulrow JP, Mulrow CD, McKenna WJ. Pyridoxine and amiodarone-induced photosensitivity. Ann Intern Med 1985;103:68-9. PubMed
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  16. Jansen T, Romiti R, Kreuter A, Altmeyer P. Rosacea fulminans triggered by high-dose vitamins B6 and B12. J Eur Acad Dermatol Venereol 2001;15:484-5..
  17. Chittumma P, Kaewkiattikun K, Wiriyasiriwach B. Comparison of the effectiveness of ginger and vitamin B6 for treatment of nausea and vomiting in early pregnancy: a randomized double-blind controlled trial. J Med Assoc Thai 2007;90:15-20.
  18. Hatzitolios, A., Iliadis, F., Katsiki, N., and Baltatzi, M. Is the anti-hypertensive effect of dietary supplements via aldehydes reduction evidence based? A systematic review. Clin Exp.Hypertens. 2008;30(7):628-639. PubMed
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  20. de, Vogel S., Dindore, V., van, Engeland M., Goldbohm, R. A., van den Brandt, P. A., and Weijenberg, M. P. Dietary folate, methionine, riboflavin, and vitamin B-6 and risk of sporadic colorectal cancer. J Nutr 2008;138(12):2372-2378. PubMed
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  22. Aybak, M., Sermet, A., Ayyildiz, M. O., and Karakilcik, A. Z. Effect of oral pyridoxine hydrochloride supplementation on arterial blood pressure in patients with essential hypertension. Arzneimittelforschung. 1995;45(12):1271-1273.
  23. Lal, K. J., Dakshinamurti, K., and Thliveris, J. The effect of vitamin B6 on the systolic blood pressure of rats in various animal models of hypertension. J Hypertens. 1996;14(3):355-363. PubMed
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  28. Mahmoud A, Tabassum S, Al Enazi S, et al. Amelioration of levetiracetam-induced behavioral side effects by pyridoxine. A randomized double blind controlled study. Pediatr Neurol 2021;119:15-21. PubMed
  29. Gupta M, Gallante B, Bamberger JN, et al. Prospective randomized evaluation of idiopathic hyperoxaluria treatments. J Endourol 2021;35(12):1844-1851. PubMed
  30. Li H, Chen M, Liang S, et al. Excessive vitamin B6 during treatment is related to poor prognosis of patients with nasopharyngeal carcinoma: A U-shaped distribution suggests low dose supplement. Clin Nutr 2021;40(4):2293-2300. PubMed
  31. Tanigawa J, Nabatame S, Tominaga K, et al. High-dose pyridoxine treatment for inherited glycosylphosphatidylinositol deficiency. Brain Dev 2021;43(6):680-687. PubMed
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See these in context on the Vitamin B6 monograph →

5-htp 32 references
  1. Birdsall TC. 5-Hydroxytryptophan: A Clinically-Effective Serotonin Precursor. Altern Med Rev 1998;3:271-80.
  2. Michelson D, Page SW, Casey R, et al. An eosinophilia-myalgia syndrome related disorder associated with exposure to L-5-hydroxytryptophan. J Rheumatol 1994;21:2261-5.
  3. Cangiano C, Ceci F, Cancino A, et al. Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophan. Am J Clin Nutr 1992;56:863-7. PubMed
  4. U.S. Food and Drug Administration. Impurities confirmed in dietary supplement 5-hydroxy-L-tryptophan. FDA Talk Paper, August 31, 1998; T98-48.
  5. Sternberg EM, Van Woert MH, Young SN, et al. Development of a scleroderma-like illness during therapy with L-5-hydroxytryptophan and carbidopa. N Engl J Med 1980;303:782-7. PubMed
  6. Poldinger W, Calanchini B, Schwarz W. A functional-dimensional approach to depression: serotonin deficiency as a target syndrome in a comparison of 5-hydroxytryptophan and fluvoxamine. Psychopathology 1991;24:53-81.
  7. Ribeiro CA. L-5-Hydroxytryptophan in the prophylaxis of chronic tension-type headache: a double-blind, randomized, placebo-controlled study. Headache 2000;40:451-6.
  8. U. S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, Office of Nutritional Products, Labeling, and Dietary Supplements. Information Paper on L-Tryptophan and 5-hydroxy-L-tryptophan, February 2001.
  9. Singhal AB, Caviness VS, Begleiter AF, et al. Cerebral vasoconstriction and stroke after use of serotonergic drugs. Neurology 2002;58:130-3. PubMed
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  26. Auffret, M., Comte, H., and Bene, J. Eosinophilia-myalgia syndrome induced by L-5 hydroxytryptophane: about three cases. Fund Clin Pharmacol 2013;Suppl 1(120):poster P2-204.
  27. Wyatt, R. J., Vaughan, T., Kaplan, J., Galanter, M., and Green, R. 5-Hydroxytryptophan and chronic schizophrenia. In: Barchas J and Usdin E. Serotonin and Behavior. New York: Acedemic Press;1973.
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Tyrosine 4 references
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Passion Flower 19 references
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Rhodiola 13 references
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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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