Vitamin D - Hydrochlorothiazide, Methyldopa Interaction
Herbal: Vitamin D
Also Known As: Ergocalciferol, Cholecalciferol
Drug: Hydrochlorothiazide, Methyldopa
Brand names:
Aldoril 15, Methazide, Aldoril 25, Aldoril D30
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 18, 2025
Interaction Details
Hydrochlorothiazide, Methyldopa is classified as belonging to the following category: Thiazide Diuretics
Theoretically, taking thiazide diuretics and high-dose vitamin D can increase the risk of hypercalcemia.
Thiazide diuretics decrease urinary calcium excretion, which could lead to hypercalcemia if vitamin D supplements are taken concurrently. This has been reported in people being treated with vitamin D for hypoparathyroidism, and also in elderly people with normal parathyroid function who were taking a thiazide, vitamin D, and calcium-containing antacids daily.
Interaction Rating
Likelihood of Occurrence
ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
References
- Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
- Crowe M, Wollner L, Griffiths RA. Hypercalcemia following vitamin D and thiazide therapy in the elderly. Practitioner 1984;228:312-3.
- Parfitt AM. Thiazide-induced hypercalcemia in vitamin D-treated hypoparathyroidism. Ann Intern Med 1972;77:557-63.
- Thiazide diuretics and the risk of osteoporosis. Pharmacist's Letter/Prescriber's Letter 2003;19(11):191105.
- Escribano, J., Balaguer, A., Pagone, F., Feliu, A., and Roque, I. Figuls. Pharmacological interventions for preventing complications in idiopathic hypercalciuria. Cochrane.Database.Syst.Rev. 2009;(1):CD004754.
Vitamin D Overview
Vitamin D is a fat-soluble vitamin that plays a crucial role in several bodily processes. It helps the body absorb calcium and phosphorus, which are necessary for healthy bones and teeth. It is also important for immune system function and may help to protect against certain diseases.
Vitamin D is found in a variety of foods, including fatty fish, egg yolks, and fortified foods such as milk and cereal. It is also produced by the body when the skin is exposed to sunlight.
Vitamin D supplements are available in a variety of forms, including tablets, capsules, and liquids. The recommended daily intake of vitamin D varies depending on age, sex, and other factors, and it is important to follow the dosage recommendations provided by a healthcare professional. There are several different forms of vitamin D available, with the two most popular being ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3).
Vitamin D - More Interactions
Vitamin D interacts with 694 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
| Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
| Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
| Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
| Unknown | No interactions have been reported or no interaction data is currently available. |
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Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC
Drug descriptions are provided by MedlinePlus.
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