Losartan and Cough
Losartan is a medication prescribed to manage high blood pressure (hypertension). It is also used in the treatment of heart failure and to reduce the risk of stroke in patients with high blood pressure and an enlarged heart. It relaxes blood vessels, lowering blood pressure and easing the heart’s pumping action.
While less common than with some other blood pressure medications, Losartan can cause a cough in some individuals. This cough is typically dry and persistent, meaning it produces no mucus and tends to linger. The incidence of cough with Losartan is relatively low, affecting only a small percentage of patients.
The Underlying Mechanism
To understand why Losartan might cause a cough, it helps to look at how it works within the body’s renin-angiotensin system. Losartan belongs to a class of drugs called Angiotensin Receptor Blockers (ARBs). These medications work by blocking the action of angiotensin II, a chemical that narrows blood vessels and increases blood pressure. By blocking angiotensin II from binding to its receptors, Losartan helps blood vessels relax and widen.
Unlike ACE inhibitors, which directly interfere with an enzyme that also breaks down bradykinin, ARBs generally do not lead to an accumulation of bradykinin. Bradykinin, when accumulated, causes the cough associated with ACE inhibitors. However, even without this direct effect on bradykinin, a small number of patients on Losartan may still develop a cough. This may be due to individual sensitivities, indirect effects on other pathways, or other less understood mechanisms.
Managing a Losartan-Related Cough
If you develop a persistent cough while taking Losartan, it is important to consult your doctor. They can help determine if the cough is related to the medication or if it stems from another cause, such as allergies, respiratory infections, or other underlying conditions. Your doctor will review your medical history and may conduct examinations to rule out other causes.
Do not stop taking Losartan or adjust your dosage without medical guidance. Your doctor may suggest monitoring the cough to see if it resolves or if it worsens over time. In some cases, they might consider adjusting your dosage or, if the cough significantly impacts your quality of life, switching you to a different class of blood pressure medication. Any decision to change medication will weigh Losartan’s benefits against the cough’s discomfort.
Losartan Versus Other Medications
When considering medications for high blood pressure, it is helpful to compare Losartan’s cough risk with that of other common treatments. Angiotensin-Converting Enzyme (ACE) inhibitors, such as lisinopril or enalapril, are another widely used class of drugs for hypertension. These medications cause a persistent dry cough in a higher percentage of patients, affecting 5% to 20% of users.
Losartan, as an ARB, is often prescribed as an alternative for patients who develop a significant cough while on an ACE inhibitor. While Losartan can still cause a cough, its incidence is significantly lower than that of ACE inhibitors. ARBs are an option for individuals needing blood pressure control who cannot tolerate the cough side effect of ACE inhibitors. The choice of medication is always individualized, based on effectiveness, side effect profiles, and patient tolerance.