Characteristics of Lisinopril-Induced Cough
Lisinopril-induced cough is characteristically a dry, persistent, nonproductive cough with a tickling or scratching sensation in the throat that worsens at night and can occur anywhere from hours after the first dose to months after starting therapy 1.
Clinical Presentation
The cough has several distinctive features that help identify it:
- Quality: Dry, nonproductive, and persistent with a tickling or scratching throat sensation 1
- Timing of onset: Can begin within hours of the first dose or be delayed for weeks to months after initiation 1
- Nocturnal worsening: Approximately 79% of patients report increased intensity at night 2, with sleep interference being common 3
- Not dose-dependent: The cough occurs regardless of lisinopril dosage 1, 2, 4
Epidemiology and Risk Factors
The incidence varies widely in reported studies:
- Overall incidence: Ranges from 5-35% in treated patients 1, though the FDA label reports cough occurring 2.5% more frequently than placebo 5
- Female predominance: Women develop ACE inhibitor-induced cough 2-3 times more frequently than men 1, 6, 2, 4. In one study, 12.6% of women vs 4.4% of men reported cough spontaneously 6
- Nonsmokers: More likely to develop cough than smokers 1, 6
- Ethnicity: Higher incidence in persons of Chinese origin 1
Diagnostic Confirmation
To confirm lisinopril as the cause, discontinue the medication regardless of the temporal relationship between starting the drug and cough onset 1. The diagnosis is confirmed by:
- Resolution timeframe: Cough typically resolves within 1-4 weeks after discontinuation 1
- Important caveat: In a subgroup of patients, resolution may be delayed up to 3 months 1
- Cough reduction pattern: 50% reduction within 3 days, complete resolution within 10 days in most cases 4
Mechanism
The cough likely results from accumulation of bradykinin and substance P (normally degraded by ACE) in the upper respiratory tract, which stimulates lung afferent C fibers and may trigger prostaglandin E2 production 1, 7.
Potential Complications
The cough can be severe enough to cause:
- Urinary stress incontinence (reported in 5 women in one series) 3
- Rectal and vaginal prolapse 3
- Significant functional impairment with some patients feeling incapacitated 3
- Sleep disruption 3
Clinical Pitfall
Do not assume the temporal relationship matters—ACE inhibitors should be considered causative in any patient with chronic cough taking these medications, even if the cough started long after drug initiation 1. Additionally, ACE inhibitor therapy may sensitize the cough reflex and potentiate other causes of chronic cough 1, so stopping the medication may still be beneficial even when other pulmonary pathology is present.