Lisinopril is a medication frequently prescribed to manage high blood pressure, also known as hypertension, and to treat heart failure. This medication belongs to a class of drugs called angiotensin-converting enzyme (ACE) inhibitors. Lisinopril works by relaxing blood vessels, which helps to lower blood pressure and reduce the workload on the heart. Its action helps to improve overall cardiovascular function for individuals with these conditions.
The Persistent Dry Cough
The most common side effect of lisinopril, and other ACE inhibitors, is a persistent dry cough. This non-productive cough, often described as a tickle in the throat, does not produce phlegm or mucus. Onset can vary, appearing days to months after starting the medication.
The cough results from lisinopril’s effect on bradykinin, a natural substance. Lisinopril inhibits the enzyme that breaks down bradykinin, causing it to accumulate in the airways. This accumulation irritates nerve endings in the respiratory tract, triggering the cough reflex. While bothersome, this cough is not dangerous and does not indicate a serious underlying condition.
Despite its benign nature, the cough can disrupt daily life and sleep. It is a frequent reason for discontinuing lisinopril. Patients should discuss this side effect with their healthcare provider, as alternative medications are available that do not cause this cough. Adjusting treatment can improve comfort while managing blood pressure or heart failure.
Other Common Side Effects
Beyond the cough, lisinopril can cause other common side effects, though less frequent. Dizziness is common, especially when standing up. This occurs due to the medication’s blood pressure-lowering effect, which temporarily reduces blood flow to the brain. Lightheadedness and fatigue are also reported, related to the body adjusting to lower blood pressure.
Headache is another side effect when starting lisinopril. Nausea and diarrhea are also possible gastrointestinal side effects. These symptoms are often mild and may lessen as the body adapts to the medication. These effects differ from the dry cough’s mechanism, stemming from different physiological responses.
When to Seek Medical Attention
While many lisinopril side effects are mild, some warrant prompt medical attention. Angioedema (swelling of the face, lips, tongue, or throat) is a rare but serious allergic reaction requiring immediate emergency care. Difficulty breathing or swallowing with swelling indicates a medical emergency. Severe dizziness or fainting spells also require immediate consultation, as they could signify an excessive drop in blood pressure.
Patients should also be aware of symptoms indicating high potassium levels (hyperkalemia), which lisinopril can cause. Signs include muscle weakness, tingling, or an irregular heartbeat. Decreased urine output or ankle swelling could signal kidney problems, necessitating medical evaluation. Never stop taking lisinopril without consulting a healthcare provider, even if side effects occur, as abrupt discontinuation can be harmful.