Warnings and Precautions With Losartan
There are several warnings and precautions with losartan to be aware of before beginning treatment. For example, you should not take losartan if you are allergic to any components of the medicine. Also, certain side effects may occur with the use of losartan, including extremely low blood pressure and decreased kidney function. The drug also poses health risks to a fetus when taken during pregnancy.
- Heart disease, including congestive heart failure
- Liver disease, including cirrhosis
- Kidney disease or kidney failure
- Any allergies, including allergies to other angiotensin II receptor blockers, foods, dyes, or preservatives.
Also, let your healthcare provider know if you are:
- Pregnant or trying to become pregnant
- On dialysis
Tell your healthcare provider about all other medicines you are currently taking, including prescription and non-prescription medicines, vitamins, and herbal supplements.
Patients taking losartan should keep the following precautions and warnings in mind:
- There are several medicines that losartan can interact with (see Drug Interactions With Losartan).
- Losartan may cause extreme low blood pressure in some people. Extreme low blood pressure is more likely to happen in people with who are taking a diuretic, are on dialysis, have diarrhea or vomiting, sweat a lot, have congestive heart failure, or have recently had a heart attack. This is why it is important to drink fluids regularly while taking losartan. If you have any possible symptoms of low blood pressure, such as dizziness, light-headedness, or fainting, contact your healthcare provider. If you have fainted, stop taking losartan until you have talked to your healthcare provider.
Also, make sure not to drive, operate any heavy machinery, or perform any other tasks that require alertness before you know how losartan affects you.
- Losartan is a pregnancy Category C medicine for the first trimester and a pregnancy Category D medicine for the second and third trimester, meaning that the drug poses health risks to your unborn child. Let your healthcare provider know if you are pregnant or thinking of becoming pregnant. If you become pregnant while taking losartan, contact your healthcare provider immediately (see Cozaar and Pregnancy for more information).
- While taking losartan, do not use potassium supplements or salt substitutes with potassium unless you have discussed this with your doctor. This is because in some people taking losartan, potassium in the blood can increase to dangerous levels.
- If you have moderate to severe liver disease, such as cirrhosis, your body may metabolize the Losartan differently than intended. Therefore, your healthcare provider may start you on a lower dose of losartan and monitor your situation more closely.
- Angiotensin II receptor blockers, including losartan, have been known to cause a decrease in kidney function, especially in certain groups of people (such as those with severe congestive heart failure). Let your healthcare provider know if you have symptoms such as a decrease in urine output, drowsiness, headache, or back pain. Your healthcare provider will also regularly check your kidney function with a blood test.
- If you are nursing, it is not known whether or not losartan passes through your milk. Therefore, if you are nursing, talk with your healthcare provider about whether you should discontinue losartan or stop breastfeeding.