Major interaction on record — check this product against your medications before combining. Based on 10 of 13 ingredients. Check your meds →
Dietary supplement

Hemp Force Active Choco Maca Ingredients & Drug Interactions

by Onnit

Hemp Force Active Choco Maca 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 Hemp Force Active Choco Maca 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

Hemp Force Active Choco Maca is a dietary supplement by Onnit with 13 active ingredients. Its ingredients are commonly taken for constipation, diarrhea, high cholesterol.Based on those ingredients, 2,151 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Dietary Fiber, Hulled Hemp, Cocoa. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Hemp Force Active Choco Maca by Onnit

Ask about any prescription or over-the-counter medication and we check it for interactions with Hemp Force Active Choco Maca by Onnit — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Hemp Force Active Choco Maca by Onnit

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 Aug 6, 2026

What’s inside

Partial disclosure
Ingredient Transparency · database check
Partial

Most active ingredients list an amount, but at least one is hidden in a blend or missing.

Why this rating?
  • The label discloses an exact amount for 8 of its 13 active ingredients.
  • “Onnit Coco Hemp Blend” is a proprietary blend — the label gives one combined amount (23,400 mg) without saying how much of each component you get.
  • “Onnit Veggie Protein Blend” is a proprietary blend — the label gives one combined amount (11,700 mg) without saying how much of each component you get.

Hemp Force Active Choco Maca is a powder with 12 active ingredients. It contains fats (polyunsaturated and monounsaturated), sodium, vitamins (C and calcium), minerals (iron), plant-based proteins (organic brown rice, organic hemp, pea, and a veggie blend), cocoa, hulled hemp, and maca root extract.

The product also includes inactive ingredients: natural flavors, stevia extract, luo han guo fruit extract, and silicon dioxide.

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: plant-based protein for workout recovery.
  • We looked for evidence on: Athletic performance, muscle recovery, post-exercise protein synthesis, resistance training adaptation.
  • The closest evidence on file: Iron is rated "Possibly Ineffective" for Athletic performance (Natural Medicines).
  • Also on file: Maca is rated "Insufficient Reliable Evidence To Rate" for Athletic performance.
  • Also on file: Cocoa is rated "Insufficient Reliable Evidence To Rate" for Athletic performance.

The individual ingredients in this product have limited established effectiveness for specific conditions. Vitamin C is effective for vitamin C deficiency and possibly effective for anemia and exercise-related respiratory infections.

Calcium is effective for kidney failure, dyspepsia, and osteoporosis. Iron is effective for iron deficiency anemia, anemia of chronic disease, and pregnancy-related iron deficiency.

The other ingredients—sodium, cocoa, rice protein, hemp protein, pea protein, and maca—either have insufficient evidence or no established effectiveness for the conditions they're commonly associated with. The product itself is marketed as a nutritional powder, so we'd recommend checking the manufacturer's intended use to see what specific health goals it targets.

The evidence, ingredient by ingredient Black Psyllium Sodium Vitamin C Calcium Iron Cocoa Hemp Rice Protein

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 10 of the 10 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 10 of 10.
  • General safety write-ups exist for 10 of 10.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

The individual ingredients are generally well tolerated at normal dietary and supplement doses. Sodium is essential in small amounts but excessive intake is linked to high blood pressure and heart strain; normal dietary sodium is fine, but avoid supplements or very high intake without medical advice.

Vitamin C is generally safe at typical doses; very high doses (above 2 grams daily) can cause abdominal cramps, diarrhea, nausea, and kidney stones in those prone to them. Calcium is well tolerated at recommended amounts; very high doses may raise concerns about prostate cancer and cardiovascular disease, though research on this is mixed.

Iron can cause abdominal pain, constipation, diarrhea, and nausea, particularly at higher doses. Cocoa contains caffeine and stimulants; in food amounts it's generally safe, but watch for headaches, nausea, and gastrointestinal discomfort.

Hemp and maca as food amounts are generally well tolerated, though rare allergic reactions to hemp seed have been reported. Rice and pea proteins are generally safe, though rare cases of enterocolitis and allergic reactions (especially in children with food sensitivities) have been documented.

Side effects, ingredient by ingredient Black Psyllium Sodium Vitamin C Calcium Iron Cocoa Hemp Rice Protein

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?
  • 8 of the 10 matched ingredients can interact with medications — Black Psyllium, Calcium, Cocoa, Iron, Vitamin C, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments; heart-rhythm medications; lithium; Parkinson's medications.
  • For scale: 2,152 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check with your pharmacist or doctor if you take any of the following: HIV integrase inhibitors (dolutegravir, elvitegravir, raltegravir)—calcium may reduce their effectiveness; blood thinners (warfarin or anticoagulants/antiplatelets)—vitamin C and hemp may interfere; blood pressure medications (antihypertensives, ACE inhibitors)—sodium, hemp, and cocoa may have additive or opposing effects; lithium—sodium can raise toxicity risk; thyroid medication (levothyroxine)—calcium, iron, and vitamin C reduce absorption; chemotherapy drugs (alkylating agents, antitumor antibiotics)—vitamin C may interfere; and quinolone antibiotics—cocoa's caffeine may increase side effects. No interactions are documented for the inactive ingredients we could check.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glancePartially disclosed formula with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.

This product is a multi-ingredient nutritional powder best suited for those looking for plant-based protein and micronutrient support. If you take any prescription medication—particularly blood pressure drugs, HIV antiretrovirals, blood thinners, thyroid medication, antibiotics, or chemotherapy—you should check your exact medications with a pharmacist or doctor before starting this product, because several ingredients interact with common drugs.

Talk with your healthcare provider before using this supplement, especially if you have high blood pressure, kidney disease, or take lithium.

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

Assessment coverage: 11 of 13 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 22, 2016.

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 Hemp Force Active Choco Maca, straight from the product label.

Brand Onnit
Barcode (UPC) 819444010175
Net contents 13.8 oz.; 390 Gram(s)
Market status On market
Date entered into DSLD Sep 22, 2016
DSLD ID 64531
Product type Other Combinations
Supplement form Powder
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy 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 Hemp Force Active Choco Maca by Onnit, 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:
39 Gram(s)
Maximum serving Sizes:
39 Gram(s)
Servings per container
10
UPC/BARCODE
819444010175
IngredientAmount% DV
Calories180 Calorie(s)--
Total Carbohydrates11 Gram(s)4%
Sugar2 Gram(s)--
Calories from Fat70 Calorie(s)--
Dietary Fiber6 Gram(s)24%
Protein16 Gram(s)32%
Saturated Fat1.5 Gram(s)8%
Polyunsaturated Fat5 Gram(s)--
Sodium41 mg2%
Vitamin C2 mg2%
Calcium50 mg5%
Iron9 mg50%
Total Fat8 Gram(s)12%
Monounsaturated Fat1 Gram(s)--
organic Brown Rice Protein0 NP--
organic Hemp Protein0 NP--
Pea Protein0 NP--
Cocoa0 NP--
Onnit Coco Hemp Blend23400 mg--
Hulled Hemp0 NP--
Onnit Veggie Protein Blend11700 mg--
Maca (root) extract1950 mg--

Other ingredients: Natural Flavors, Stevia (leaf) extract, Luo Han Guo (fruit) extract, Silicon Dioxide

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

Suggested Use: As a dietary supplement, mix one scoops of powder with at least 12 ounces of water or your choice of juice.

Precautions

Consult a medical doctor before taking this or any other nutritional supplement if you are pregnant, nursing, have or suspect a medical condition or are taking any medications.

General Statements

The decadent chocolate flavor comes from pure cacao and is enhanced by one of the most sought-after performance foods in the world: maca.

Hemp FORCE Active contains a blend of delicious earth grown nutrients designed to optimize an active lifestyle.

Delicately sweetened with stevia, this low glycemic, high fiber protein makes insanely delicious smoothies and more. Go to www.HempForceRecipes.com for a full list of creative ideas, guaranteed to please your taste buds.

Plant-Based Protein

Typical Values, Natural Variation Possible

Total Human Optimization

Formula

Yielding 16 grams of plant protein from organic hemp, organic brown rice, and peas, Hemp FORCE Active is a plant-based protein supplement perfect to help you recover from or prepare for a workout.

16 g Protein 6 g Fiber with Cocoa & Maca

16g Protein 6g Fiber 3 Omega 6 Omega 9 Omega

Formulation

Vegan

Non GMO no Dairy no Gluten no Soy

FDA Statement of Identity

Dietary Supplement

General

R160203-125

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

See for yourself

Hemp Force Active Choco Maca by Onnit label

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

Hemp Force Active Choco Maca 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 Hemp Force Active Choco Maca by Onnit

These are the 13 active ingredients this product is made of. Select any to open its full monograph.

Serving size39 Gram(s) Dosage formPowder 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.

Sugar

2 Gram(s) per serving

Dietary Fiber

Interacts with
2,025 drugs
6 Gram(s) per serving

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. I...

Dietary Fiber monograph & interactions

Protein

16 Gram(s) per serving

Sodium

Interacts with
205 drugs
41 mg per serving

Sodium is an essential mineral and electrolyte your body needs to balance fluids, support nerves, and help muscles work. Most people in modern diets g...

Sodium monograph & interactions

Vitamin C

Interacts with
207 drugs
2 mg per serving

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

Calcium

Interacts with
168 drugs
50 mg per serving

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet f...

Calcium monograph & interactions

Iron

Interacts with
80 drugs
9 mg per serving

Iron is an essential mineral your body needs to make hemoglobin and carry oxygen in the blood. Supplements are mainly useful for treating or preventin...

Iron monograph & interactions

Onnit Coco Hemp Blend

23400 mg per serving

Onnit Veggie Protein Blend

11700 mg per serving

Maca (root) extract

No known
interactions
1950 mg per serving

Maca is a nutrient-rich Andean root often used for energy, libido, and menopause symptoms. Early studies suggest it may modestly help sexual desire an...

Maca (root) extract monograph & interactions

Other (inactive) ingredients: Natural Flavors, Stevia (leaf) extract, Luo Han Guo (fruit) extract, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Hemp Force Active Choco Maca by Onnit Drug Interactions

Want to check YOUR meds against Hemp Force Active Choco Maca?

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
2,151Drugs
7 Major 788 Moderate 1,356 Minor

Ingredients driving the most interactions

Dietary Fiber 2,025
Hulled Hemp 938
Cocoa 661
Vitamin C 207
Sodium 205

Individual Drug Interactions

The ingredients in Hemp Force Active Choco Maca interact with 2,151 drugs. Click any drug to see the details.

8 of the 13 ingredients in Hemp Force Active Choco Maca interact with drugs. Each result below shows which ingredient is responsible. Dietary Fiber Hulled Hemp Cocoa Vitamin C Sodium Calcium Iron organic Brown Rice Protein

Each ingredient & the kinds of drugs it affects

For each ingredient in Hemp Force Active Choco Maca 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.

Dietary Fiber7 drug types · 2,025 drugs

Carbamazepine (Tegretol)

Theoretically, black psyllium might reduce the effects of carbamazepine and increase the risk for convulsions.
Theoretically, black psyllium might reduce carbamazepine absorption. A preliminary study using blond psyllium reported decreased carbamazepine bioavailability due to binding of the drug to psyllium, as well as reduction of available fluid in the gut for dissolution of the drug. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Lithium

Theoretically, taking black psyllium at the same time as lithium might reduce lithium absorption.
The fiber in black psyllium might reduce lithium absorption and plasma levels. Some case reports describe a reduction in plasma lithium levels with concomitant administration of blond psyllium. This was reversed when psyllium was stopped. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Metformin (Glucophage)

Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Animal research shows that concurrent consumption of blond psyllium with metformin slows and increases the absorption of metformin. This interaction may also occur with black psyllium. To avoid changes in absorption, take psyllium 30-60 minutes after metformin.

Likelihood Possible Evidence D
Olanzapine (Zyprexa)

Theoretically, taking black psyllium at the same time as olanzapine might reduce olanzapine absorption.
The fiber in black psyllium might decrease the absorption of olanzapine. A single case report describes a reduction in the effectiveness of olanzapine when it was concomitantly administered with an unspecified type of psyllium 3 grams orally twice daily. This effect was reversed when psyllium was stopped.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, taking black psyllium at the same time as digoxin might reduce digoxin absorption and decrease digoxin levels.
Psyllium might bind digoxin in the gut. However, some clinical evidence suggests that psyllium does not impact digoxin absorption.

Likelihood Unlikely Evidence B
Ethinyl Estradiol

Theoretically, taking black psyllium at the same time as ethinyl estradiol might alter levels of estradiol.
Concurrent use of blond psyllium with ethinyl estradiol results in a slight increase in the extent of ethinyl estradiol absorption and a slower rate of absorption. This is unlikely to be clinically significant.

Likelihood Unlikely Evidence D
Oral Drugs

Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Psyllium seems to have variable effects on drug absorption. To avoid changes in absorption, take psyllium 30-60 minutes after oral medications. Animal research shows that blond psyllium delays and increases the absorption of metformin and ethinyl estradiol. Case reports and animal research suggest that blond psyllium might reduce absorption of lithium, digoxin, olanzapine, and carbamazepine. Finally, some pharmacokinetic studies show that psyllium does not affect the absorption of levothyroxine or warfarin. Although many of these studies evaluated blond psyllium, the fiber content in black psyllium may have similar effects.

Likelihood Possible Evidence B
Dietary Fiber full monograph & interactions

Hulled Hemp6 drug types · 938 drugs

Estrogens

Theoretically, hemp might interfere with hormone therapy due to its estrogenic effects.
In an ovariectomized animal model, a diet containing hemp seed 1%, 2%, or 10% resulted in normalized plasma levels of 17-beta-estradiol. The mechanism of action for this effect is unclear.

Likelihood Possible Evidence D
Ace Inhibitors (Aceis)

Theoretically, consuming hemp seed protein isolate with ACE inhibitors might have additive effects and increase the risk of hypotension.
Hemp seed protein hydrolysate has shown ACE inhibitor-like effects in a hypertensive animal model. However, hempseed oil consumption does not seem to reduce blood pressure in humans. Until more is known, monitor blood pressure and potassium levels.

Likelihood Unlikely Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, hemp seed might increase the risk of bleeding when used concomitantly with anticoagulant/antiplatelet drugs.
In animal research, hemp seed at 5% of the diet inhibits platelet aggregation in vitro. However, in human research, taking hemp seed oil 2 grams daily for 12 weeks does not inhibit the aggregation of platelets in vitro.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, hemp seed protein may have additive effects with antihypertensive drugs.
In a hypertensive animal model, hemp seed protein hydrolysate reduced systolic blood pressure by a mechanism possibly involving the inhibition of renin and angiotensin converting enzyme (ACE) activities. However, there was no effect of hemp seed protein on blood pressure in normotensive animals. Furthermore, hempseed oil consumption does not seem to reduce blood pressure in humans.

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

Theoretically, hemp might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research shows that hemp induces CYP1A2 enzymes.

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

Theoretically, hemp might decrease the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that hemp induces CYP3A4 enzymes.

Likelihood Possible Evidence D
Hulled Hemp full monograph & interactions

Cocoa37 drug types · 661 drugs

Ace Inhibitors (Aceis)

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

Likelihood Possible Evidence D
Adenosine (Adenocard)

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

Likelihood Possible Evidence B
Alcohol (Ethanol)

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

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

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

Likelihood Possible Evidence D
Antihypertensive Drugs

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

Likelihood Possible Evidence D
Beta-Adrenergic Agonists

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

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

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

Likelihood Possible Evidence D
Dipyridamole (Persantine)

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

Likelihood Probable Evidence B
Disulfiram (Antabuse)

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

Likelihood Probable Evidence B
Diuretic Drugs

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

Likelihood Possible Evidence D
Ephedrine

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

Likelihood Possible Evidence D
Estrogens

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

Likelihood Probable Evidence B
Flutamide (Eulexin)

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

Likelihood Possible Evidence D
Fluvoxamine (Luvox)

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

Likelihood Probable Evidence D
Lithium

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

Likelihood Possible Evidence D
Monoamine Oxidase Inhibitors (Maois)

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

Likelihood Possible Evidence D
Nicotine

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

Likelihood Probable Evidence B
Pentobarbital (Nembutal)

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

Likelihood Possible Evidence B
Phenobarbital (Luminal)

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

Likelihood Possible Evidence D
Phenylpropanolamine

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

Likelihood Probable Evidence B
Phenytoin (Dilantin)

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

Likelihood Possible Evidence D
Quinolone Antibiotics

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

Likelihood Probable Evidence B
Riluzole (Rilutek)

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

Likelihood Possible Evidence D
Stimulant Drugs

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

Likelihood Probable Evidence C
Theophylline

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

Likelihood Probable Evidence B
Cocoa full monograph & all 37 interactions

Vitamin C13 drug types · 207 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.

Likelihood Probable Evidence B
Antitumor Antibiotics

Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.

Likelihood Probable Evidence B
Warfarin (Coumadin)

High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Salsalate (Disalcid)

Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Vitamin C full monograph & interactions

Sodium7 drug types · 205 drugs

Antihypertensive Drugs

Theoretically, a high intake of dietary sodium might reduce the effectiveness of antihypertensive drugs.
High intake of dietary sodium can increase systolic and diastolic blood pressure. Also, high intake of sodium may necessitate increased use of antihypertensive medications to achieve blood pressure control in some patients, such as those with chronic kidney disease.

Likelihood Probable Evidence A
Corticosteroids

Concomitant use of mineralocorticoids and some glucocorticoids with sodium supplements might increase the risk of hypernatremia.
Mineralocorticoids and some glucocorticoids (corticosteroids) cause sodium retention. This effect is dose-related and depends on mineralocorticoid potency. It is most common with hydrocortisone, cortisone, and fludrocortisone, followed by prednisone and prednisolone.

Likelihood Possible Evidence D
Didanosine (Videx)

Concomitant use of didanosine with additional sodium from dietary or supplemental sources may increase the risk of hypernatremia.
Didanosine formulations contain a significant amount of sodium.

Likelihood Probable Evidence C
Lithium

Altering dietary intake of sodium might alter the levels and clinical effects of lithium.
High sodium intake can reduce plasma concentrations of lithium by increasing lithium excretion. Reducing sodium intake can significantly increase plasma concentrations of lithium and cause lithium toxicity in patients being treated with lithium carbonate. Stabilizing sodium intake is shown to reduce the percentage of patients with lithium level fluctuations above 0.8 mEq/L. Patients taking lithium should avoid significant alterations in their dietary intake of sodium.

Likelihood Probable Evidence B
Sodium Phosphates

Theoretically, concomitant use of sodium phosphate with sodium supplements might increase the risk of hypernatremia.
Use of high doses (> 45 mL in 24 hours) of sodium phosphate, such as those used for bowel cleansing before surgery, can lead to serious electrolyte disturbances, including hypernatremia. The risk of hypernatremia is highest in the elderly and people with other risk factors for electrolyte disturbances.

Likelihood Possible Evidence D
Sodium-Containing Drugs

Concomitant use of sodium-containing drugs with additional sodium from dietary or supplemental sources may increase the risk of hypernatremia and long-term sodium-related complications.
The Chronic Disease Risk Reduction (CDRR) intake level of 2.3 grams of sodium daily indicates the intake at which it is believed that chronic disease risk increases for the apparently healthy population. Some medications contain high quantities of sodium. When used in conjunction with sodium supplements or high-sodium diets, the CDRR may be exceeded. Additionally, concomitant use may increase the risk for hypernatremia; this risk is highest in the elderly and people with other risk factors for electrolyte disturbances.

Likelihood Possible Evidence D
Tolvaptan (Samsca)

Theoretically, concomitant use of tolvaptan with sodium might increase the risk of hypernatremia.
Tolvaptan is a vasopressin receptor 2 antagonist that is used to increase sodium levels in patients with hyponatremia. Patients taking tolvaptan should use caution with the use of sodium salts such as sodium chloride.

Likelihood Probable Evidence C
Sodium full monograph & interactions

Calcium18 drug types · 168 drugs

Ceftriaxone (Rocephin)

Co-administration of intravenous calcium and ceftriaxone can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys.
Avoid administering intravenous calcium in any form, such as parenteral nutrition or Lactated Ringers, within 48 hours of intravenous ceftriaxone. Case reports in neonates show that administering intravenous ceftriaxone and calcium can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys. In several cases, neonates have died as a result of this interaction. So far there are no reports in adults; however, there is still concern that this interaction might occur in adults.

Likelihood Probable Evidence D
Dolutegravir (Tivicay)

Calcium seems to reduce levels of dolutegravir.
Advise patients to take dolutegravir either 2 hours before or 6 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium carbonate 1200 mg concomitantly with dolutegravir 50 mg reduces plasma levels of dolutegravir by almost 40%. Calcium appears to decrease levels of dolutegravir through chelation.

Likelihood Probable Evidence B
Elvitegravir (Vitekta)

Calcium seems to reduce levels of elvitegravir.
Advise patients to take elvitegravir either 2 hours before or 2 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium along with elvitegravir can reduce blood levels of elvitegravir through chelation.

Likelihood Probable Evidence B
Aluminum

Calcium citrate might increase aluminum absorption and toxicity. Other types of calcium do not increase aluminum absorption.
Calcium citrate can increase the absorption of aluminum when taken with aluminum hydroxide. The increase in aluminum levels may become toxic, particularly in individuals with kidney disease. However, the effect of calcium citrate on aluminum absorption is due to the citrate anion rather than calcium cation. Calcium acetate does not appear to increase aluminum absorption.

Likelihood Possible Evidence B
Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Calcium might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and calcium can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, calcium containing products.

Likelihood Probable Evidence D
Bisphosphonates

Calcium reduces the absorption of bisphosphonates.
Advise patients to take bisphosphonates at least 30 minutes before calcium, but preferably at a different time of day. Calcium supplements decrease absorption of bisphosphonates.

Likelihood Probable Evidence C
Calcipotriene (Dovonex)

Taking calcipotriene with calcium might increase the risk for hypercalcemia.
Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriene with calcium supplements might increase the risk of hypercalcemia.

Likelihood Possible Evidence B
Digoxin (Lanoxin)

Using intravenous calcium with digoxin might increase the risk of fatal cardiac arrhythmias.
Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. However, one retrospective analysis of clinical data suggests that intravenous calcium does not increase the risk of dysrhythmias or mortality in patients receiving digoxin.

Likelihood Possible Evidence B
Diltiazem (Cardizem, Others)

Theoretically, calcium may reduce the therapeutic effects of diltiazem.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, calcium might increase this risk of hypercalcemia and reduce the effectiveness of diltiazem.

Likelihood Probable Evidence D
Levothyroxine (Synthroid, Others)

Calcium seems to reduce the absorption and effectiveness of levothyroxine.
Advise patients to take levothyroxine and calcium supplements at least 4 hours apart. Calcium reduces levothyroxine absorption, probably by forming insoluble complexes. Calcium carbonate supplements reduce effectiveness of levothyroxine in patients with hypothyroidism.

Likelihood Probable Evidence B
Lithium

Theoretically, concomitant use of calcium and lithium may increase this risk of hypercalcemia.
Clinical research suggests that long-term use of lithium may cause hypercalcemia in 10% to 60% of patients. Theoretically, concomitant use of lithium and calcium supplements may further increase this risk.

Likelihood Possible Evidence B
Quinolone Antibiotics

Calcium seems to reduce the absorption of quinolone antibiotics.
Advise patients to take oral quinolones at least 2 hours before or 4-6 hours after calcium supplements or calcium-fortified foods. Taking calcium at the same time as oral quinolones can reduce quinolone absorption. Calcium binds to quinolones in the gut.

Likelihood Probable Evidence B
Raltegravir (Isentress)

Calcium may reduce levels of raltegravir.
Pharmacokinetic research shows that taking a single dose of calcium carbonate 3000 mg along with raltegravir 400 mg twice daily modestly decreases the mean area under the curve of raltegravir, but the decrease does not necessitate a dose adjustment of raltegravir. However, a case of elevated HIV-1 RNA levels and documented resistance to raltegravir has been reported for a patient taking calcium carbonate 1 gram three times daily plus vitamin D3 (cholecalciferol) 400 IU three times daily in combination with raltegravir 400 mg twice daily for 11 months. It is thought that calcium reduced raltegravir levels by chelation, leading to treatment failure.

Likelihood Possible Evidence B
Sotalol (Betapace)

Calcium seems to reduce the absorption of sotalol.
Advise patients to separate doses by at least 2 hours before or 4-6 hours after calcium. Calcium appears to reduce the absorption of sotalol, probably by forming insoluble complexes.

Likelihood Possible Evidence B
Tetracycline Antibiotics

Calcium seems to reduce the absorption of tetracycline antibiotics.
Advise patients to take oral tetracyclines at least 2 hours before, or 4-6 hours after calcium supplements. Taking calcium at the same time as oral tetracyclines can reduce tetracycline absorption. Calcium binds to tetracyclines in the gut.

Likelihood Probable Evidence C
Thiazide Diuretics

Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Thiazides reduce calcium excretion by the kidneys. Using thiazides along with moderately large amounts of calcium carbonate increases the risk of milk-alkali syndrome (hypercalcemia, metabolic alkalosis, renal failure). Patients may need to have their serum calcium levels and/or parathyroid function monitored regularly.

Likelihood Probable Evidence C
Verapamil (Calan, Others)

Theoretically, calcium may reduce the therapeutic effects of verapamil.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, use of calcium supplements may increase this risk of hypercalcemia and reduce the effectiveness of verapamil.

Likelihood Probable Evidence D
Calcium Channel Blockers

Intravenous calcium may decrease the effects of calcium channel blockers; oral calcium is unlikely to have this effect.
Intravenous calcium is used to decrease the effects of calcium channel blockers in the management of overdose. Intravenous calcium gluconate has been used before intravenous verapamil (Isoptin) to prevent or reduce the hypotensive effects without affecting the antiarrhythmic effects. But there is no evidence that dietary or supplemental calcium when taken orally interacts with calcium channel blockers.

Likelihood Unlikely Evidence D
Calcium full monograph & interactions

Iron13 drug types · 80 drugs

Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Iron might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and iron can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, iron containing products.

Likelihood Probable Evidence D
Bisphosphonates

Iron reduces the absorption of bisphosphonates.
Advise patients that doses of bisphosphonates should be separated by at least two hours from doses of all other medications, including supplements such as iron. Divalent cations, including iron, can decrease absorption of bisphosphonates by forming insoluble complexes in the gastrointestinal tract.

Likelihood Probable Evidence D
Denosumab (Prolia, Others)

Administration of intravenous iron within one month of denosumab administration might increase the risk of severe hypophosphatemia and hypocalcemia.
A case of severe hypocalcemia (albumin corrected calcium 6.88 mg/dL, ionized calcium 3.68 mg/dL) and hypophosphatemia (<0.5 mg/dL) with respiratory acidosis, QT interval prolongation, and nonsustained ventricular tachycardia was reported in a 76-year-old male who had received an iron polymaltose infusion within 2 weeks of a subcutaneous injection of denosumab. Serum parathyroid hormone was also elevated (348 pg/mL). Subsequent iron infusions with iron polymaltose and ferric carboxymaltose were followed by transient hypophosphatemia, but without hypocalcemia. Additionally, a literature review describes 6 additional cases of hypophosphatemia and hypocalcemia in patients 52-92 years of age who had been administered intravenous iron as either ferric carboxymaltose or iron polymaltose and subcutaneous denosumab within 1-4 weeks of each other.

Likelihood Possible Evidence D
Dolutegravir (Tivicay)

Iron might decrease dolutegravir levels by reducing its absorption.
Advise patients to take dolutegravir at least 2 hours before or 6 hours after taking iron. Pharmacokinetic research shows that iron can decrease the absorption of dolutegravir from the gastrointestinal tract through chelation. When taken under fasting conditions, a single dose of ferrous fumarate 324 mg orally along with dolutegravir 50 mg reduces overall exposure to dolutegravir by 54%.

Likelihood Probable Evidence B
Integrase Inhibitors

Theoretically, taking iron along with integrase inhibitors might decrease the levels and clinical effects of these drugs.
Iron is a divalent cation. There is concern that iron may decrease the absorption of integrase inhibitors from the gastrointestinal tract through chelation. One pharmacokinetic study shows that iron can decrease blood levels of the specific integrase inhibitor dolutegravir through chelation. Also, other pharmacokinetic research shows that other divalent cations such as calcium can decrease the absorption and levels of some integrase inhibitors through chelation.

Likelihood Possible Evidence D
Levodopa

Iron might decrease levodopa levels by reducing its absorption.
Advise patients to separate doses of levodopa and iron as much as possible. There is some evidence in healthy people that iron forms chelates with levodopa, reducing the amount of levodopa absorbed by around 50%. The clinical significance of this hasn't been determined.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Iron might decrease levothyroxine levels by reducing its absorption.
Advise patients to separate levothyroxine and iron doses by at least 2 hours. Iron can decrease the absorption and efficacy of levothyroxine by forming insoluble complexes in the gastrointestinal tract.

Likelihood Probable Evidence B
Methyldopa (Aldomet)

Iron might decrease methyldopa levels by reducing its absorption.
Advise patients to separate methyldopa and iron doses by at least 2 hours. Iron can decrease the absorption of methyldopa from the gastrointestinal tract through chelation, resulting in increases in blood pressure.

Likelihood Probable Evidence B
Mycophenolate Mofetil (Cellcept)

Theoretically, iron might decrease mycophenolate mofetil levels by reducing its absorption.
Advise patients to take iron 4-6 hours before, or 2 hours after, mycophenolate mofetil. It has been suggested that a decrease of absorption is possible, probably by forming nonabsorbable chelates. However, mycophenolate pharmacokinetics are not affected by iron supplementation in available clinical research.

Likelihood Unlikely Evidence D
Penicillamine (Cuprimine, Depen)

Iron might decrease penicillamine levels by reducing its absorption.
Advise patients to separate penicillamine and iron doses by at least 2 hours. Oral iron supplements can reduce absorption of penicillamine by 30% to 70%, probably due to chelate formation. In people with Wilson's disease, this interaction has led to reduced efficacy of penicillamine.

Likelihood Probable Evidence D
Quinolone Antibiotics

Iron might decrease levels of quinolone antibiotics by reducing their absorption.
Advise patients to separate quinolone antibiotics and iron doses by at least 2 hours. Iron decreases the absorption of quinolones due to formation of insoluble complexes in the gastrointestinal tract.

Likelihood Probable Evidence D
Tetracycline Antibiotics

Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Advise patients to take iron at least 2 hours before or 4 hours after tetracycline antibiotics. Concomitant use can decrease absorption of tetracycline antibiotics from the gastrointestinal tract by 50% to 90%.

Likelihood Probable Evidence D
Chloramphenicol

Theoretically, taking chloramphenicol with iron might reduce the response to iron therapy in iron deficiency anemia.
Chloramphenicol interferes with erythrocyte maturation. However, since chloramphenicol isn't usually taken for prolonged periods, this isn't likely to be clinically significant.

Likelihood Unlikely Evidence D
Iron full monograph & interactions

organic Brown Rice Protein1 drug type · 23 drugs

Ace Inhibitors (Aceis)

In laboratory research, hydrolyzed rice protein inhibits angiotensin-converting enzyme (ACE). In animal research, the inhibition of ACE is correlated with a reduction in systolic blood pressure. So far, this effect has not been shown in humans. Theoretically, concomitant use of rice protein and ACE inhibitors may increase the risk of blood pressure becoming too low. Use with caution. ACE inhibitors include benazepril (Lotensin), captopril (Capoten), enalapril (Vasotec), fosinopril (Monopril), lisinopril (Prinivil, Zestril), moexipril (Univasc), perindopril (Aceon), quinapril (Accupril), ramipril (Altace), and trandolapril (Mavik).

Likelihood Possible Evidence D
organic Brown Rice Protein full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Hemp Force Active Choco Maca, from the product label.

Onnit

See all Onnit products
Name
Onnit Labs, LLC
City
Austin
State
Texas
ZipCode
78744
Phone Number
(855) 666-4899
Pharmacist Counseling Corner

Hemp Force Active Choco Maca by Onnit: Common Questions

Does Hemp Force Active Choco Maca by Onnit interact with any medications?
Yes. Based on its ingredients, Hemp Force Active Choco Maca has a known interaction with 2,151 medications, including 7 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Hemp Force Active Choco Maca contains 13 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Does this powder contain caffeine?
Yes, because it contains cocoa, which has caffeine. The exact amount isn't listed here, so check the nutrition label or product packaging for the caffeine content per serving.
Is this safe if I'm pregnant?
Safety data is mixed across ingredients. Calcium and iron are generally considered likely safe at recommended amounts in pregnancy, but maca should be avoided due to insufficient data. Check with your doctor or prenatal care provider before starting—they can personalize advice based on your complete medical history.
Can I take this if I'm breastfeeding?
Most of the ingredients are likely fine in food or moderate supplement amounts, but maca and concentrated hemp extracts haven't been well studied during breastfeeding. Cocoa's caffeine does pass into breast milk, so keep that in mind. Talk with your healthcare provider before starting.
What is maca supposed to do?
Maca is traditionally used for sexual function, energy, and fertility, but the evidence to support these uses is currently insufficient. The data we hold doesn't establish that it works for any specific condition.
Is this a complete meal replacement?
No, this is a nutritional powder with protein and micronutrients, not a meal replacement. It's designed to supplement your diet, not replace whole foods or balanced meals.
Does this contain any allergens?
It contains plant proteins (hemp, rice, pea) and cocoa. Rare allergic reactions to hemp seed and pea protein have been documented, particularly in people with existing food sensitivities. Check the full ingredient list on the label for all allergen warnings.

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

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Hemp Force Active Choco Maca label
Go deeper

The Full Monographs Behind Hemp Force Active Choco Maca’s Ingredients

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

Herb & supplement monograph

Black Psyllium

Interacts with 2,025 drugs

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. It is best known and most studied for rel...

Read the full Black Psyllium monograph → Herb & supplement monograph

Sodium

Interacts with 205 drugs

Sodium is an essential mineral and electrolyte your body needs to balance fluids, support nerves, and help muscles work. Most people in modern diets get more than enough—often too much—from...

Read the full Sodium monograph → Herb & supplement monograph

Vitamin C

Interacts with 207 drugs

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...

Read the full Vitamin C monograph → Herb & supplement monograph

Calcium

Interacts with 168 drugs

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet falls short. Most people do best getting...

Read the full Calcium monograph → Herb & supplement monograph

Iron

Interacts with 80 drugs

Iron is an essential mineral your body needs to make hemoglobin and carry oxygen in the blood. Supplements are mainly useful for treating or preventing iron deficiency and iron-deficiency an...

Read the full Iron monograph → Herb & supplement monograph

Cocoa

Interacts with 661 drugs

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

Read the full Cocoa monograph → Herb & supplement monograph

Hemp

Interacts with 938 drugs

Hemp seeds and hemp seed oil are nutritious foods rich in protein, fiber, and healthy omega-3 and omega-6 fatty acids, and they are generally safe for most people as part of the diet. While...

Read the full Hemp monograph → Herb & supplement monograph

Rice Protein

Interacts with 23 drugs

Rice protein is a plant-based protein powder made from rice that offers an easy way to add protein to your diet, especially if you avoid dairy or animal products. It is generally considered...

Read the full Rice Protein monograph → Herb & supplement monograph

Pea Protein

Pea protein is a plant-based protein powder made from yellow split peas, commonly used by people who want a dairy-free or vegan source of protein to support muscle and overall protein intake...

Read the full Pea Protein monograph → Herb & supplement monograph

Maca

Maca is a nutrient-rich Andean root often used for energy, libido, and menopause symptoms. Early studies suggest it may modestly help sexual desire and some menopause symptoms, but the evide...

Read the full Maca monograph →
Sources

Sources & How We Checked

Hemp Force Active Choco Maca'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 380 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.

Black Psyllium 18 references
  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
  4. Etman M. Effect of a bulk forming laxative on the bioavailablility of carbamazepine in man. Drug Dev Ind Pharm 1995;21:1901-6.
  5. Perlman BB. Interaction between lithium salts and ispaghula husk. Lancet 1990;335:416.
  6. Vaswani SK, Hamilton RG, Valentine MD, Adkinson NF. Psyllium laxative-induced anaphylaxis, asthma, and rhinitis. Allergy 1996;51:266-8. PubMed
  7. Lantner RR, Espiritu BR, Zumerchik P, Tobin MC. Anaphylaxis following ingestion of a psyllium-containing cereal. JAMA 1990;264:2534-6. DOI
  8. Kaplan MJ. Anaphylactic reaction to "Heartwise." N Engl J Med 1990;323:1072-3. DOI
  9. Nordstrom M, Melander A, Robertsson E, Steen B. Influence of wheat bran and of a bulk-forming ispaghula cathartic on the bioavailability of digoxin in geriatric in-patients. Drug Nutr Interact 1987;5:67-9..
  10. Robinson DS, Benjamin DM, McCormack JJ. Interaction of warfarin and nonsystemic gastrointestinal drugs. Clin Pharmacol Ther 1971;12:491-5. PubMed
  11. Garcia JJ, Fernandez N, Diez MJ, et al. Influence of two dietary fibers in the oral bioavailability and other pharmacokinetic parameters of ethinyloestradiol. Contraception 2000;62:253-7. PubMed
  12. Fernandez N, Lopez C, Díez R, et al. Drug interactions with the dietary fiber Plantago ovata husk. Expert Opin Drug Metab Toxicol 2012;8(11):1377-86.
  13. Semen plantaginis in: WHO Monographs on Selected Medicinal Plants, volume 1. World Health Organization, Geneva, 1999. Available at http://apps.who.int/medicinedocs/en/d/Js2200e/. Accessed November 26, 1026.
  14. Code of Federal Regulations, Title 21 (21CFR 101.17). Food labeling warning, notice, and safe handling statements. Available at www.ecfr.gov/cgi-bin/text-idx?SID=20f647d3b74161501f46564b915b4048&mc=true&node=se21.2.101_117&rgn=div8. Accessed December 3, 2
  15. Code of Federal Regulations, Title 21 (21CFR 201.319). Specific labeling requirements - water-soluble gums, hydrophilic gums, and hydrophilic mucilloids. Available at www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=201.319. Accessed Dece
  16. Diez R, Garcia JJ, Diez MJ, Sierra M, Sahagun AM, Fernandez N. Influence of Plantago ovata husk (dietary fiber) on the bioavailability and other pharmacokinetic parameters of metformin in diabetic rabbits. BMC Complement Altern Med. 2017 Jun 7;17(1):298. PubMed
  17. Chiu AC, Sherman SI. Effects of pharmacological fiber supplements on levothyroxine absorption. Thyroid. 1998;8(8):667-71. PubMed
  18. Merrick C, Madden CA, Capurso NA. A Case of Blunted Orally Disintegrating Olanzapine Effect Due to Coadministered Psyllium. J Clin Psychiatry 2021;82(2):20cr13633. PubMed

See these in context on the Black Psyllium monograph →

Sodium 38 references
  1. Garabedian-Ruffalo SM, Ruffalo RL. Drug and nutrient interactions. Am Fam Physician 1986;33:165-74.
  2. Food and Drug Administration Science Background: Safety of Sodium Phosphates Oral Solution. September 17, 2001. Available at: http://www.fda.gov/cder/drug/safety/sodiumphospate.htm
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Iron 72 references
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Maca 1 reference
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