Losartan Not Working After Lisinopril Switch

In our latest question and answer, the pharmacist compares two medications for blood pressure, losartan and lisinopril.

Aug 01, 2018

Molly asked

I was on Lisinopril for more than 5 years and my doctor switched me to Losartan 3 days ago because the Lisonopril was giving me a very bad dry cough! My blood pressure readings have been very high which is not normal when I was taking Lisinopril. What should I do? My Losartan dosage is 25mg/per day. Lisinopril was 20mg/per day with a reading range between 120/80 sometimes 130/85. Now its readings of 140/90 or this morning was 144/111 What should I do, because it's only been 3 days? Please advise. Should I notify her immediately?

Answer

We wrote an article very similar to your situation, which can be found here: Switching From Losartan to Lisinopril.

Some highlights of the article include:

  • Lisinopril is an ACE-Inhibitor (angiotension converting enzyme inhibitor) while losartan is an ARB (angiotension receptor blocker).
  • ACE-Inhibitors are strongly associated with causing a dry, unproductive cough. For this reason, it is a common need to switch to an ARB medication, like losartan, as they are less associated with causing a cough (1).
  • When switching between lisinopril and losartan, there is no specific conversion chart. Choice of strength is more a matter of the dosage range of each drug...whether you were on a low, medium or high dose.

Dosage Range For Lisinopril And Losartan

  • Lisinopril has a dosage range from 10 to 80 mg. The usual starting dose is 10 mg with the most common effective dose range is from 20-40 mg.
  • Losartan has a dosage range from 25 to 100 mg. The usual starting dose is 50 mg .

Unless there are other factors to your medical situation, it is important to try and find the optimal dose of losartan before switching back to lisinopril and potentially putting you at risk for the side effects you were experiencing.

According to the prescribing information for losartan, the 50 mg dose produces statistically significant deceases to both systolic and diastolic blood pressure when compared to the 25 mg dose (2). Your dose may just be too low! 50 mg of losartan is the usual starting dose for the drug and you simply need to increase your dose over time to find an effective one.

It is important to keep track of your blood pressure readings and discuss them with your doctor so your therapy can be adjusted and optimized appropriately.

Ready for a more personal experience with your meds?