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.
Sodium Phenylbutyrate, Taurursodiol
5 nutrient associations Full Sodium Phenylbutyrate, Taurursodiol report →BETA-CAROTENE
Insignificant DepletionBILE ACID SEQUESTRANTS
Cholestyramine (Questran) and colestipol (Colestid) can reduce absorption of fat-soluble vitamins, including beta-carotene. Serum levels of beta-carotene can be reduced, but this is probably only in proportion to the lowering of cholesterol (on which beta-carotene is transported). Supplements are not usually needed.
What Vitamin A does & food sources
Vitamin A supports vision, immune function, and skin health.
Common food sources:
- Liver and fish oils
- Dairy and eggs
- Orange and yellow vegetables (as beta-carotene)
- Leafy greens
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
What to discuss with your clinician
Ask your provider before supplementing vitamin A — status testing is not routine, and intake from food plus multivitamins is often already adequate.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Supplement considerations
Vitamin A is fat-soluble and accumulates; excess is harmful (and dangerous in pregnancy). Prefer food sources unless a clinician advises otherwise.
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 vitamin A in pregnancy or when trying to conceive unless a clinician directs it.
References (5)
- Hathcock JN. Metabolic mechanisms of drug-nutrient interactions. Fed Proc 1985;44:124-9.
- Elinder LS, Hadell K, Johansson J, et al. Probucol treatment decreases serum concentrations of diet-derived antioxidants. Arterioscler Thromb Vasc Biol 1995;15:1057-63. PubMed
- Knodel LC, Talbert RL. Adverse effects of hypolipidaemic drugs. Med Toxicol 1987;2:10-32. PubMed
- Tonstad S, Silverstein M, Aksnes L, Ose L. Low dose colestipol in adolescents with familial hypercholesterolemia. Arch Dis Child 1996;74:157-60.
- Matsui MS, Rozovski SJ. Drug-nutrient interaction. Clin Ther 1982;4:423-40.
VITAMIN B12
Insignificant DepletionBILE ACID SEQUESTRANTS
These resins can decrease gastrointestinal (GI) absorption of vitamin B12 by binding intrinsic factor and vitamin B12-intrinsic factor complexes. However, absorption isn't completely prevented. It's unlikely that this interaction will deplete body stores of vitamin B12 unless there are other factors contributing to deficiency. In a group of children treated with cholestyramine for up to 2.5 years, there was no change in serum vitamin B12 levels. Routine supplements aren't necessary.
What Vitamin B12 does & food sources
Vitamin B12 supports red blood cell formation, nerve function, and DNA synthesis.
Common food sources:
- Meat, poultry, and fish
- Eggs and dairy products
- Fortified cereals and nutritional yeast
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
What to discuss with your clinician
If you take an associated medication long-term, ask your healthcare provider whether checking a vitamin B12 level (sometimes with methylmalonic acid) is appropriate — especially if you notice fatigue, numbness, tingling, or memory changes.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Supplement considerations
B12 status is easy to check and low levels are usually straightforward to address, so testing before supplementing is often the sensible order. High-dose folic acid can mask a B12 deficiency, which is one reason B12 and folate questions are best sorted out together with your provider.
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: B12 deficiency can look like other conditions — do not self-diagnose from symptoms alone.
References (3)
- Coronato A, Glass GB. Depression of the intestinal uptake of radio-vitamin B12 by cholestyramine. Proc Soc Exp Biol Med 1973;142:1341-4. DOI
- Leonard JP, Desager JP, Beckers C, Harvengt C. In vitro binding of various biological substances by two hypocholesterolemic resins. Arzneimittelforschung 1979;29:97-81.
- West RJ, Lloyd JK. The effect of cholestyramine on intestinal absorption. Gut 1975;16:93-8. PubMed
VITAMIN E
Insignificant DepletionBILE ACID SEQUESTRANTS
Cholestyramine (Questran) and colestipol (Colestid) reduce absorption of dietary fat, so there is concern that they might reduce absorption of fat soluble vitamins, including vitamin E. Some studies suggest that the bile acid sequestrants lower vitamin E levels by 7% to 20%. But other studies have found no effect on vitamin E levels. When decreases did occur, they were often in proportion to the lowering of LDL (on which vitamin E is transported), and did not fall below the lower limit of normal (5 micrograms/mL) with up to 2 years of treatment. Routine vitamin E supplements aren't necessary, but consider them for patients who take high doses of bile acid sequestrants for several years, or who have low serum vitamin E levels.
What Vitamin E does & food sources
Vitamin E is a fat-soluble antioxidant that protects cell membranes.
Common food sources:
- Vegetable oils
- Nuts and seeds
- Wheat germ
- Leafy greens
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
What to discuss with your clinician
Deficiency is rare; ask your provider before supplementing, particularly if you take blood thinners.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Supplement considerations
Higher-dose vitamin E can increase bleeding tendency, especially with warfarin or antiplatelet medications.
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: Discuss vitamin E supplements with your provider if you take any blood thinner.
References (7)
- West RJ, Lloyd JK. The effect of cholestyramine on intestinal absorption. Gut 1975;16:93-8. PubMed
- Cywes C, Millar AJ. Assessment of the nutritional status of infants and children with biliary atresia. S Afr Med J 1990;77:131-5.
- Elinder LS, Hadell K, Johansson J, et al. Probucol treatment decreases serum concentrations of diet-derived antioxidants. Arterioscler Thromb Vasc Biol 1995;15:1057-63. PubMed
- Schwarz KB, Goldstein PD, Witztum JL, et al. Fat-soluble vitamin concentrations in hypercholestrolemic children treated with colestipol. Pediatrics 1980;65:243-50.
- Tonstad S, Silverstein M, Aksnes L, Ose L. Low dose colestipol in adolescents with familial hypercholesterolemia. Arch Dis Child 1996;74:157-60.
- Schade RWB, van't Laar A, Majoor CLH, Jansen AP. A comparative study of the effects of cholestyramine and neomycin in the treatment of type II hyperlipoproteinemia. Acta Med Scand 1976;199:175-80..
- Glueck CJ, Tsang RC, Fallat RW, Scheel D. Plasma vitamin A and E levels in children with familial type II hyperlipoproteinemia during therapy with diet and cholestyramine resin. Pediatrics 1974;54:51-5.. DOI
VITAMIN A
Moderate DepletionBILE ACID SEQUESTRANTS
By reducing absorption of dietary fats, cholestyramine (Questran) and colestipol (Colestid) may also reduce absorption of fat-soluble vitamins such as vitamin A. Some studies have reported a fall in serum vitamin A levels, but they rarely fall below the normal range with therapy of up to 2 years' duration. Since some of the vitamin A in plasma is carried on lipids, part of this fall in plasma vitamin A levels may be due to decreased plasma lipid levels. Other studies have reported no change in plasma vitamin A levels with colestipol, up to 30 grams/day for 6 months, or cholestyramine 12 to 24 grams/day for up to 10 years. Routine vitamin A supplements aren't necessary in people taking bile acid sequestrants, but check vitamin A levels in people taking high doses for more than 2 years. For information on foods that are rich in vitamin A, see our chart.
What Vitamin A does & food sources
Vitamin A supports vision, immune function, and skin health.
Common food sources:
- Liver and fish oils
- Dairy and eggs
- Orange and yellow vegetables (as beta-carotene)
- Leafy greens
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
What to discuss with your clinician
Ask your provider before supplementing vitamin A — status testing is not routine, and intake from food plus multivitamins is often already adequate.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Supplement considerations
Vitamin A is fat-soluble and accumulates; excess is harmful (and dangerous in pregnancy). Prefer food sources unless a clinician advises otherwise.
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 vitamin A in pregnancy or when trying to conceive unless a clinician directs it.
References (8)
- West RJ, Lloyd JK. The effect of cholestyramine on intestinal absorption. Gut 1975;16:93-8. PubMed
- Elinder LS, Hadell K, Johansson J, et al. Probucol treatment decreases serum concentrations of diet-derived antioxidants. Arterioscler Thromb Vasc Biol 1995;15:1057-63. PubMed
- Schwarz KB, Goldstein PD, Witztum JL, et al. Fat-soluble vitamin concentrations in hypercholestrolemic children treated with colestipol. Pediatrics 1980;65:243-50.
- Tonstad S, Silverstein M, Aksnes L, Ose L. Low dose colestipol in adolescents with familial hypercholesterolemia. Arch Dis Child 1996;74:157-60.
- Schade RWB, van't Laar A, Majoor CLH, Jansen AP. A comparative study of the effects of cholestyramine and neomycin in the treatment of type II hyperlipoproteinemia. Acta Med Scand 1976;199:175-80..
- Glueck CJ, Tsang RC, Fallat RW, Scheel D. Plasma vitamin A and E levels in children with familial type II hyperlipoproteinemia during therapy with diet and cholestyramine resin. Pediatrics 1974;54:51-5.. DOI
- Probstfield JL, Lin TL, Peters J, Hunninghake DB. Carotenoids and vitamin A: the effect of hypocholesterolemic agents on serum levels. Metabolism 1985;34:88-91. PubMed
- Lipid Research Clinics Program. The Lipid Research Clinics' Coronary Primary Prevention Trial Results: 1. Reduction in incidence of coronary heart disease. JAMA 1984;251:351-64. DOI
VITAMIN K
Moderate DepletionBILE ACID SEQUESTRANTS
By reducing absorption of dietary fats, bile acid sequestrants may also reduce absorption of fat-soluble vitamins such as vitamin K. Some studies have found no changes in vitamin K levels or prothrombin times after up to 2 years of bile acid sequestrant use. However, there are a few case reports of hypoprothrombinemia and bleeding, usually in people with other risk factors.
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 (5)
- West RJ, Lloyd JK. The effect of cholestyramine on intestinal absorption. Gut 1975;16:93-8. PubMed
- Schwarz KB, Goldstein PD, Witztum JL, et al. Fat-soluble vitamin concentrations in hypercholestrolemic children treated with colestipol. Pediatrics 1980;65:243-50.
- Schade RWB, van't Laar A, Majoor CLH, Jansen AP. A comparative study of the effects of cholestyramine and neomycin in the treatment of type II hyperlipoproteinemia. Acta Med Scand 1976;199:175-80..
- Knodel LC, Talbert RL. Adverse effects of hypolipidaemic drugs. Med Toxicol 1987;2:10-32. PubMed
- Vroonhof K, van Rijn HJ, van Hattum J. Vitamin K deficiency and bleeding after long-term use of cholestyramine. Neth J Med 2003;61:19-21.
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.