Does My Medication Cause Nutrient Depletion?
Some prescription and over-the-counter medications can lower your levels of important vitamins and minerals over time. Search your medication below to see what it may deplete — with evidence ratings and what to discuss with your pharmacist.
Potential nutrient considerations for your selected medication
1 medication checked · 5 nutrients with reported associations. These are talking points for your care team — not a diagnosis.
Isoniazid, Pyrazinamide, Rifampin
5 nutrient associations Full Isoniazid, Pyrazinamide, Rifampin report →NIACIN
Moderate DepletionISONIAZID
Isoniazid can cause a deficiency of pyridoxine, which is needed for conversion of tryptophan to niacin, resulting in a secondary niacin deficiency. Isoniazid also has structural similarities to niacin and might interfere with niacin's conversion to nicotinamide adenine dinucleotide (NAD). Pellagra can occur in people taking isoniazid chronically, especially if dietary niacin intake is low. It can be prevented or reversed with niacin or niacinamide supplements.
What Vitamin B3 (niacin) does & food sources
Niacin supports energy metabolism, skin health, and nervous system function.
Common food sources:
- Poultry, beef, and fish
- Peanuts and legumes
- Fortified grains
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
What to discuss with your clinician
Deficiency is rare in a typical diet. Discuss with your provider before using niacin as a supplement — at pharmacologic doses it behaves like a medication.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Supplement considerations
High-dose niacin causes flushing and can affect the liver, blood sugar, and uric acid — it is not a casual supplement.
Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Caution: Treat high-dose niacin as a medication decision, not a nutrition one.
References (6)
- Shils ME, Olson JA, Shike M, Ross AC, eds. Modern Nutrition in Health and Disease. 9th ed. Baltimore, MD: Williams & Wilkins, 1999.
- Ishii N, Nishihara Y. Pellagra encephalopathy among tuberculous patients: its relation to isoniazid therapy. J Neurol Neurosurg Psychiatry 1985;48:628-34. PubMed
- 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
- Darvay A, Basarab T, McGregor JM, Russell-Jones R. Isoniazid induced pellagra despite pyridoxine supplementation. Clin Exp Dermatol 1999;24:167-9. PubMed
- Stratigos JD, Katsambas A. Pellagra: a still existing disease. Br J Dermatol 1977;96:99-106. PubMed
- Bender DA, Russell-Jones R. Isoniazid-induced pellagra despite vitamin B6 supplementation (letter). Lancet 1979;2:1125-6. PubMed
NIACINAMIDE
Moderate DepletionPYRAZINAMIDE
There have been case reports of pellagra after pyrazinamide use which responded to niacinamide supplementation.
What Vitamin B3 (niacin) does & food sources
Niacin supports energy metabolism, skin health, and nervous system function.
Common food sources:
- Poultry, beef, and fish
- Peanuts and legumes
- Fortified grains
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
What to discuss with your clinician
Deficiency is rare in a typical diet. Discuss with your provider before using niacin as a supplement — at pharmacologic doses it behaves like a medication.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Supplement considerations
High-dose niacin causes flushing and can affect the liver, blood sugar, and uric acid — it is not a casual supplement.
Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Caution: Treat high-dose niacin as a medication decision, not a nutrition one.
References (1)
- Jorgensen J. Pellagra probably due to pyrazinamide: development during combined chemotherapy of tuberculosis. Int J Dermatol 1983;22:44-5. PubMed
VITAMIN B6
Moderate DepletionISONIAZID
Isoniazid interacts with vitamin B6 to form an inactive hydrazine, which inhibits pyridoxal kinase and increases vitamin B6 excretion in the urine. This depletes body stores of vitamin B6 and can lead to peripheral neuritis. It is rare in people receiving up to 5 mg/kg daily isoniazid. With higher doses of isoniazid, consider vitamin B6 supplements, 40-250 mg daily, especially in people with a history of seizures, and in those with other risk factors for neuropathies, including malnutrition, uremia, diabetes, alcoholism, or liver disease. For information on foods that are rich in vitamin B6, see our chart.
What Vitamin B6 does & food sources
Vitamin B6 is involved in protein metabolism, neurotransmitter production, and red blood cell formation.
Common food sources:
- Poultry and fish
- Potatoes and starchy vegetables
- Bananas
- Fortified cereals
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
What to discuss with your clinician
With some medications (for example, isoniazid), B6 is intentionally co-prescribed — follow your prescriber's plan. Otherwise, ask whether testing or supplementation is appropriate if you have symptoms like numbness or tingling.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Supplement considerations
Paradoxically, long-term high-dose B6 can itself cause nerve symptoms — this is a nutrient where more is definitely not better.
Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Caution: Avoid high-dose B6 without medical guidance; sustained high intakes can cause neuropathy.
References (5)
- Shils ME, Olson JA, Shike M, Ross AC, eds. Modern Nutrition in Health and Disease. 9th ed. Baltimore, MD: Williams & Wilkins, 1999.
- Matsui MS, Rozovski SJ. Drug-nutrient interaction. Clin Ther 1982;4:423-40.
- Bass JB, Farer LS, Hopewell PC, et al. Treatment of tuberculosis and tuberculosis infection in adults and children. Am J Respir Crit Care Med 1994;149:1359-74..
- Pellock JM, Howell J, Kendig EI Jr, et al. Pyridoxine deficiency in children treated with isoniazid. Chest 1985;87:658-61. PubMed
- Snider DE Jr. Pyridoxine supplementation during isoniazid therapy. Tubercle 1980;61:191-6. PubMed
VITAMIN D
Moderate DepletionRIFAMPIN (Rifadin)
Rifampin increases hepatic metabolism of 25-hydroxy-vitamin D, reducing its plasma levels. This can contribute to osteomalacia after prolonged therapy (>1 year), especially if vitamin D intake is low. However, if isoniazid (INH, Nydrazid) is taken concurrently with rifampin there doesn't seem to be any change in vitamin D status. This may be because the enzyme-inducing effects on rifampin are canceled out by the enzyme-inhibiting effects of isoniazid. For information on foods that are rich in vitamin D, see our chart.
What Vitamin D does & food sources
Vitamin D helps the body absorb calcium and supports bone, muscle, and immune health.
Common food sources:
- Fatty fish (salmon, mackerel)
- Fortified milk and cereals
- Egg yolks
- Sunlight exposure (the main natural source)
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
What to discuss with your clinician
A 25-hydroxyvitamin D blood test is the standard way to assess status — ask whether it is appropriate if you take an associated medication long-term, have limited sun exposure, or have bone concerns.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Supplement considerations
Vitamin D dosing varies a lot between people; some medications change how vitamin D is processed. Your provider can target a dose to your level instead of guessing.
Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Caution: Vitamin D is fat-soluble and can accumulate — very high doses over time can cause harm, so follow a clinician-guided plan.
References (5)
- Williams SE, Wardman AG, Taylor GA, et al. Long term study of the effect of rifampicin and isoniazid on vitamin D metabolism. Tubercle 1985;66:49-54. PubMed
- Kovacs CS, Jones G, Yendt ER. Primary hyperparathyroidism masked by antituberculous therapy-induced vitamin D deficiency. Clin Endocrinol (Oxf) 1994;41:831-8. PubMed
- Perry W, Erooga MA, Brown J, Stamp TC. Calcium metabolism during rifampicin and isoniazid therapy for tuberculosis. J R Soc Med 1982;75:533-6. PubMed
- Shah SC, Sharma RK, Hemangini, Chitle AR. Rifampicin induced osteomalacia. Tubercle 1981;62:207-9. PubMed
- Brodie MJ, Boobis AR, Hillyard CJ, et al. Effect of rifampicin and isoniazid on vitamin D metabolism. Clin Pharmacol Ther 1982;32:525-30. PubMed
VITAMIN K
Moderate DepletionRIFAMPIN (Rifadin)
There are occasional reports of vitamin K deficiency associated with rifampin therapy, leading to prolonged clotting times and, in one case, a cerebral bleed. Suggested mechanisms include reduced intestinal absorption of vitamin K, destruction of vitamin K-producing intestinal bacteria, and interference with enzymes that regenerate vitamin K from its inactive metabolite. Symptomatic vitamin K deficiency is most likely to occur in people with poor dietary intake or other contributory factors. For information on foods that are rich in vitamin K, see our chart.
What Vitamin K does & food sources
Vitamin K is required for normal blood clotting and contributes to bone health.
Common food sources:
- Leafy green vegetables (spinach, kale, broccoli)
- Vegetable oils
- Fermented foods like natto
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
What to discuss with your clinician
If you take warfarin, vitamin K intake is a central part of your therapy — consistency matters more than avoidance. Discuss any planned change in vitamin K intake (diet or supplements) with the clinic that manages your INR.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Supplement considerations
Never start or stop a vitamin K supplement on your own if you take warfarin — it directly changes how the medication works.
Do not start or stop medications or supplements without professional guidance — supplements can interact with prescription medications.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Caution: Vitamin K interacts with warfarin: keep intake consistent and involve your anticoagulation clinic in any change.
References (2)
- Kobayashi K, Haruta T, Maeda H, et al. Cerebral hemorrhage associated with vitamin K deficiency in congenital tuberculosis treated with isoniazid and rifampin. Pediatr Infect Dis J 2002;21:1088-90. PubMed
- Van Steenbergen W, Vermylen J. Reversible hypoprothrombinemia in a patient with primary biliary cirrhosis treated with rifampicin. Am J Gastroenterol 1995;90:1526-8.
This tool is educational and is not a substitute for professional medical advice. An association is not a diagnosis and does not mean a deficiency will occur. Always talk to your pharmacist or healthcare provider before starting, stopping, or changing any medication or supplement.
Disclaimer: This checker finds which nutrients might be depleted by prescription or over-the-counter medications. Each nutrient depletion issue is rated based on clinical significance. Use your own professional judgment prior to making clinical decisions.© 2026 Therapeutic Research Center Licensed records refresh weekly · last updated July 3, 2026.
What drug-induced nutrient depletion means
Some medications can, over time, lower the levels of certain vitamins, minerals, or other nutrients — through reduced absorption, increased loss, or changes in how the body uses them.
Association is not deficiency
An entry here means a depletion has been reported or studied — not that it happens to everyone, or that you are deficient. Dose, duration, diet, and your own health all matter.
Evidence varies by pair
Some drug–nutrient links (like metformin and vitamin B12) are well studied; others rest on limited or preliminary research. Each entry shows the evidence rating from our licensed clinical database.
When to ask about labs
If you take an associated medication long-term, ask your healthcare provider whether monitoring is appropriate for you. Not everyone needs testing — your provider can weigh your dose, duration, and symptoms.
Don't self-supplement blindly
Supplements are not risk-free: some can interact with medications, and some (like potassium or magnesium) can be risky with kidney disease. Talk to your pharmacist before adding anything.
Never stop a medication over this
These medications are prescribed for good reasons, and the benefit usually far outweighs a manageable nutrient consideration. Any change belongs in a conversation with your prescriber.
Food first, usually
For many nutrients, a varied diet covers the gap. Each entry lists common food sources; a supplement is a decision to make with your pharmacist or provider, not a default.
Nutrient depletion FAQs
Can medications really deplete nutrients?
Does an entry in this checker mean I am deficient?
Should I take a supplement if my medication appears here?
What labs should I ask about?
Can supplements interact with my medications?
Where does this information come from, and how is it reviewed?
Not sure what your results mean?
Ask a licensed pharmacist — free, no appointment needed.
Sources & How We Checked
Nutrient depletion records are evidence-graded and sourced from the Natural Medicines database, and are displayed as published with their citations. The plain-English education is written and reviewed by licensed HelloPharmacist pharmacists.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference for drug-induced nutrient depletions, supplements, and interactions — the basis for this checker.
- MedlinePlus, U.S. National Library of Medicine — NIH consumer drug information, used for medication overviews across the site.
Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.