MEDICATIONS can cause weight gain

As a nutrition support pharmacist, patients often ask you if their MEDICATIONS can cause weight gain. And alternatives to these medications may need to be considered, especially for patients who are overweight or obese with diabetes, etc...

• Atypical antipsychotics are notorious for causing weight gain, which might increase the risk of diabetes or cardiovascular disease. Clozapine (Leponex, Clozapex) and olanzapine (Zyprexa, Olapex) are the biggest offenders while aripiprazole (Abilify) and ziprasidone (Geodon) the least. About 75% of patients on olanzapine gain weight up to 10 pounds (4.5 kg) in 10 weeks. But some patients gain much more with long-term use. 
• Consider prescribing an alternative if a patient gains more than 5% of their original weight. Adding metformin (Glucophage) might also help limit weight gain if the offending drug can't be changed.
• Mood stabilizers can also increase weight in patients. Up to 20% of patients on lithium gain 20 pounds or more. About half of patients on valproic acid (Depakene) have a 10% increase in weight. This is more likely to happen in women. If possible, use carbamazepine (Tegretol) or lamotrigine (Lamictal) for less weight gain.
• Many antidepressants increase weight. The most likely are MAO inhibitors, tricyclics, and mirtazapine (Remeron). SSRIs are okay for short-term use, but weight gain may occur when they're used for more than 6 months. Consider bupropion (Wellbutrin, Abastain), venlafaxine (Effexor), or duloxetine (Cymbalta) if weight gain is a concern.
• Hormonal contraception SOMETIMES leads to weight gain. Oral contraceptives (OCs) can initially increase weight due to edema, but long-term gains aren't likely. Depo-Provera can lead to about an 11 pound (5 kg) increase over 5 years.
• Diabetes agents, especially hypoglycemics like sulfonylureas (Amaryl, etc) or insulin, can also lead to weight gain. And glitazones (Actos, etc) can cause fluid retention. Prescribe metformin (Glucophage) instead.
• Antihistamines and corticosteroids may also increase weight. Use intranasal or inhaled products to limit weight gain. Talk with patients so they are not surprised and stop needed medications over fear of weight gain. GET OUR NOTE, "Consider alternatives to medications that can lead to significant weight gain".

REFERENCES

• Malone M. Medications associated with weight gain. Ann Pharmacother. 2005 Dec;39(12):2046-55. Available at: https://journals.sagepub.com/doi/10.1345/aph.1G333. Or, https://pubmed.ncbi.nlm.nih.gov/16278256

  Apovian CM, Aronne LJ, Bessesen DH, McDonnell ME, Murad MH, Pagotto U, Ryan DH, Still CD; Endocrine Society. Pharmacological management of obesity: an endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2015 Feb;100(2):342-62. Available at: https://pubmed.ncbi.nlm.nih.gov/25590212