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- What is losartan, and how does it work (mechanism of action)?
- What brand names are available for losartan?
- Is losartan available as a generic drug?
- Do I need a prescription for losartan?
- What are the side effects of losartan?
- What is the dosage for losartan?
- Which drugs or supplements interact with losartan?
- Is losartan safe to take if I'm pregnant or breastfeeding?
- What else should I know about losartan?
What is losartan, and how does it work (mechanism of action)?
Losartan is an oral medication that belongs to a class of drugs called angiotensin receptor blockers (ARBs). Other ARBs include irbesartan (Avapro), valsartan (Diovan), and candesartan (Atacand). Angiotensin formed in the blood by the action of angiotensin converting enzyme (ACE) is a powerful chemical that attaches to angiotensin receptors found in many tissues but primarily on smooth muscle cells of blood vessels. Angiotensin's attachment to the receptors causes the muscle cells to contract and the blood vessels to narrow (vasoconstrict) which leads to an increase in blood pressure (hypertension). Losartan (more specifically, the chemical formed when the liver converts the inactive losartan into its active form) blocks the angiotensin receptor. By blocking the action of angiotensin, losartan relaxes muscle cells and dilates blood vessels thereby reducing blood pressure.
Losartan was approved by the FDA in April 1995.
What brand names are available for losartan?
Is losartan available as a generic drug?
GENERIC AVAILABLE: Yes
Do I need a prescription for losartan?
What are the side effects of losartan?
Side effects reported included:
Losartan also may cause:
Losartan may reduce kidney function in some patients and should not be used by patients who have bilateral renal artery stenosis (narrowing of both arteries going to the kidneys).
Rare cases of rhabdomyolysis (muscle breakdown) have been reported.
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