Chlorpromazine & Nutrient Depletion
Also searched as Thorazine, Thorazine Spansules. What the clinical evidence reports, what it may mean, and what to discuss with your pharmacist.
Chlorpromazine has been associated with depletion of RIBOFLAVIN. This does not mean a deficiency will occur — it means these are worth knowing about and, if you take Chlorpromazine long-term, worth raising with your pharmacist or healthcare provider.
Take more than one medication? Open the checker with Chlorpromazine pre-loaded and add the rest to see overlapping nutrient signals.
Reported nutrient depletions with Chlorpromazine
Each record below is shown as published in our licensed clinical database, with its evidence rating and citations. Expand a section for food sources and talking points.
RIBOFLAVIN
Insufficient EvidenceCHLORPROMAZINE (Thorazine)
Chlorpromazine has structural similarities to riboflavin and can interfere with its conversion to the active form, flavin adenine dinucleotide (FAD). In rats, chlorpromazine decreases FAD levels in the liver, kidneys, heart and skeletal muscle, increases urinary riboflavin excretion, and produces changes in erythrocyte enzyme activity consistent with riboflavin deficiency. Chlorpromazine also inhibits renal tubular secretion and reabsorption of riboflavin. Although these effects occur in rats at similar doses to those used in humans, data in humans are lacking. There isn't enough evidence to recommend use of riboflavin supplements with chlorpromazine or other phenothiazines.
Riboflavin (vitamin B2) helps your body produce energy and keeps your skin, nerves, and red blood cells working properly. Chlorpromazine is chemically shaped in a way that may interfere with how the body converts riboflavin into its active, usable form, and it may also affect how the kidneys handle riboflavin. That said, this has really only been studied in animals, and there is not enough human data to know whether it matters at a practical level. Most people taking chlorpromazine do not need to act on this right now, but if you have questions or take this medication long-term, it is worth a quick conversation with your pharmacist or doctor.
What Vitamin B2 (riboflavin) does & food sources
Riboflavin helps the body produce energy and process other B vitamins.
Common food sources:
- Dairy products and eggs
- Lean meats
- Fortified grains
- Green vegetables
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
What to discuss with your clinician
Deficiency is uncommon with a varied diet; ask your provider if you have persistent mouth-corner cracking, sore tongue, or unexplained fatigue on a long-term associated medication.
HelloPharmacist pharmacist-reviewed education — separate from the licensed record above.
Supplement considerations
Riboflavin is water-soluble and excess is excreted (it turns urine bright yellow — harmless).
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.
Learn more about this nutrient: Riboflavin — uses, safety & interactions
References (5)
- Pinto J, Huang YP, Rivlin RS. Inhibition of riboflavin metabolism in rat tissues by chlorpromazine, imipramine and amitriptyline. J Clin Invest 1981;67:1500-6. PubMed
- Pinto J, Huang YP, Pelliccione N, Rivlin RS. Cardiac sensitivity to the inhibitory effects of chlorpromazine, imipramine, and amitriptyline upon formation of flavins. Biochem Pharmacol 1982;31:3495-9.. PubMed
- Pelliccione N, Pinto J, Huang YP, Rivlin RS. Accelerated development of riboflavin deficiency by treatment with chlorpromazine. Biochem Pharmacol 1983;32:2949-53.. PubMed
- Raiczyk GB, Dutta P, Pinto J. Chlorpromazine and quinacrine inhibit flavin adenine dinucleotide biosynthesis in skeletal muscle. Physiologist 1985;28:322.
- Yanagawa N, Shih RN, Jo OD, Said HM. Riboflavin transport by isolated perfused rabbit renal proximal tubules. Am J Physiol Cell Physiol 2000;279:C1782-6.. PubMed
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.
More about Chlorpromazine
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.
Chlorpromazine & nutrients: FAQs
Does Chlorpromazine deplete RIBOFLAVIN?
Should I take a supplement because I take Chlorpromazine?
Should I stop taking Chlorpromazine?
Where does this information come from?
Questions about Chlorpromazine and your nutrition?
Ask a licensed pharmacist — free, no appointment needed.
Sources & How We Checked
Nutrient depletion records for Chlorpromazine are evidence-graded and sourced from the Natural Medicines database, and are displayed as published with their citations.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference for drug-induced nutrient depletions, supplements, and interactions — the basis for this page.
- 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.