Do antihistamines cause weight gain?
Some antihistamines, especially older types, have been linked to weight gain in studies, but evidence is not clear-cut and mostly shows an association rather than direct cause. Newer antihistamines commonly used in the UK are unlikely to cause significant weight changes. Speak to your GP or pharmacist if concerned about weight changes while taking them.
Key points:
- Older first-generation antihistamines may contribute to weight gain through effects on appetite.
- Newer second-generation antihistamines show low risk of weight gain.
- Studies often find links between antihistamine use and higher weight, but cannot prove cause.
- Long-term use might increase risk more than short-term use.
This text has been fact-checked for accuracy by medino's clinical team.