Educational Content: This article is for informational purposes only and does not constitute medical advice. Always consult a healthcare provider for diagnosis and treatment.

Which Medications Cause the Most Weight Gain?

Medically reviewed by Min Clinic Staff | Updated: January 2026

Weight loss eludes you despite you eating right and exercising daily. Medications that may be associated with weight gain include antidepressants, steroids, diabetes medications, mood stabilizers, blood pressure medications, seizure medications, migraine medications, antiretroviral medications, contraceptives and others.
Weight loss eludes you despite you eating right and exercising daily. Medications that may be associated with weight gain include antidepressants, steroids, diabetes medications, mood stabilizers, blood pressure medications, seizure medications, migraine medications, antiretroviral medications, contraceptives and others.

Your weight loss eludes you despite you eating right and exercising daily. What might be the cause? Well, the medicines you take may often be the culprits behind your unreasonable weight gain. Here are some medicines that can cause weight gain if you take them regularly.

Antidepressant medications: Weight gain is a well-known side effect of many drugs given for mood disorders.

Steroid medications:

Diabetes medications:

  • The anabolic effect (promoting protein and fat storage) of these medications can cause weight gain.
  • Many oral medications used to treat type II diabetes (sulfonylureas and thiazolidinediones) and insulin may encourage weight gain. Common diabetes medications that may contribute to weight gain include

    Antiretroviral medications:

    • These medications are used for treating human immunodeficiency virus (HIV). There are various types that work in various ways.
    • Typically, people with HIV take three or more of these medications together or these medications can be combined into a single pill. Unfortunately, they are also linked with unavoidable weight gain.

    Others: Antihistamines such as Allegra, Zyrtec and Periactin and medications taken for hyperthyroidism (radioactive iodine and oral antithyroid medications such as carbimazole).

    You should talk to your healthcare provider about drugs and weight gain. If weight gain is a concern, ask your doctor to substitute your medicine. Doctors and obesity researchers say that weight gain is associated with a few categories or families of drugs, not necessarily some specific brands. Moreover, not everyone who takes these medicines puts on pounds. Happily, people who do usually have an alternative medication they can try.