A dry and often bothersome cough is the most common adverse effect of ACE inhibitors. Recent studies indicate that cough may develop in ~10% of the patients treated with ACE inhibitors.
WHY? Mechanism unknown. It is thought to likely involve the protussive mediators: 1) bradykinin and 2) substance P. Normally they would be degraded by ACE and when using ACEi they accumulate in the lungs causing a cough.
REFERENCES
- Dicpinigaitis PV. Angiotensin-converting enzyme inhibitor-induced cough: ACCP evidence-based clinical practice guidelines. Chest. 2006 Jan;129(1 Suppl):169S-173S.