Losartan Potassium (Antihypertensive)

Question 1

What is the brand name of Losartan Potassium?

Answer 1

Cozaar

Question 2

What strength tablets are available for Cozaar?

Answer 2

25mg, 50mg, 100mg

Question 3

What dose of Cozaar is approved to treat hypertension?

Answer 3

Usual starting dose is 50mg QD with 25mg used in patients with possible depletion of intravascular volume. Can be administered QD or BID with total daily doses ranging from 25mg to 100mg. If BP is not controlled, one may consider adding a low dose diuretic

Question 4

What dose of Losartan Potassium is used to reduce the risk of stroke in patients with HTN & left ventricular hypertrophy?

Answer 4

Start with 50mg QS. Based on BP response, add HCTX or increase to 100mg/day following by an increase in HCTZ to 25mg/day.

Question 5

What dose of Cozaar is used to treat diabetic neuropathy with an elevated serum creatinine & proteinuria? (>300mg/day) in patients with type 2 diabetes and HTN?

Answer 5

Start with 50mg/day QD. Increase to 100mg QD based on BP response

Question 6

What should the providers monitor in patients taking Cozaar?

Answer 6

CrCl, Blood Pressure, Potassium

Question 7

What is the mechanism of action for Cozaar?

Answer 7

Angiotensin II is a potent vasoconstrictor. Losartan blocks the binding sites of angiotensin II by blocking the vasoconstrictor and lodestone-secreting effects of angiotensin II

Question 8

What are the drug interactions of Losartan?

Answer 8

• Coadministration of cimetidine has led to an increase of about 18% in AUC of losartan but did not affect the PK of the active metabolite.
• Coadministration of Phenobarbital led to a reduction of about 20% in the AUC of losartan and that of its active metabolite
• NSAIDs, including COX-2 inhibitors, may decrease effects and increase risk of renal function deterioration
• Increased adverse affects may occur when used with other renin-angiotensin system blockers or aliskiren

Question 9

What are the contraindications of Losartan?

Answer 9

• Contraindicated with aliskiren
• DO NOT USE DURING PREGNANCY
• Use with caution in nursing mothers
• Drugs that act directly on the renin-angiotensin system can cause fetal & neonatal morbidity and death when administered to pregnant women.
• In patients who are intravenously volume-depleted symptomatic hypotension may occur after initiation of therapy w/ losartan.
• A lower dose should be considered for patients with impaired liver function
• Use with caution in patients with impaired renal function
• Pregnancy Category D

Question 10

What are the adverse effects of Cozaar?

Answer 10

The most common adverse effects are upper respiratory infections, diarrhea, dizziness, nasal congestion, and cough. Rare cases of rhabdomyolysis have been reported in patients receiving angiotensin II receptor blockers.

Question 11

What should the RPh tell the patient when counseling on Losartan Potassium/Cozaar?

Answer 11

• May be taken with or without food
• When pregnancy is detected, losartan should be DC ASAP
• Contact a physician if adverse effects become severe
• If a dose is missed, skip it & return to normal schedule