High levels of antihistamine drugs can reduce fitness gains, study finds

[Nelson Vergel]

These articles discuss how histamine-blocking drugs, often taken for allergies, can negatively impact the physiological benefits of exercise. Both sources present studies indicating that high doses of antihistamines interfere with muscle adaptation, blood flow increases, and overall fitness gains from aerobic activity. While one article details a specific University of Oregon study from 2025 focusing on cycling, the other references earlier research from 2021 by Ghent University and the University of Copenhagen that examined both short-term and long-term effects across different types of antihistamines. Crucially, both pieces highlight that histamine is a vital molecule for the body's adaptive response to exercise-induced stress and inflammation, which contributes to muscle repair and growth, though more research is needed to determine the effects of typical over-the-counter antihistamine doses.

Histamine-suppressing drugs found to reduce benefits of exercise

A team of researchers from Ghent University and the University of Copenhagen has found that antihistamines such as Allegra or Pepcid can reduce the benefits of exercise. In their paper published in the journal Science Advances, the group describes two experiments they conducted—one short range...

medicalxpress.com

High levels of antihistamine drugs can reduce fitness gains, study finds

For some, the word "histamine" might evoke thoughts of seasonal allergies: runny noses, scratchy throats and itchy eyes. But the molecule also influences exercise performance.

medicalxpress.com

 

[WhiteMale]

Use of L-Histadine got me off all the OTC allergy meds I was depending on. Almost entirely. Avoiding benadryl/diphenhydramine has helped some with ED, too.