Losartan Regret, Stopping, and Restarting: What Real Patients Learn the Hard Way

At a glance

• Approved uses / hypertension in adults and children 6 and older; stroke risk reduction with hypertension and LVH (the label says there is evidence this benefit does not apply to Black patients); diabetic nephropathy with elevated creatinine and proteinuria in type 2 diabetes with hypertension [1]
• Usual adult hypertension dose / 50 mg once daily; maximum 100 mg once daily [1]
• Lower starting dose / 25 mg once daily with possible intravascular depletion or mild-to-moderate hepatic impairment [1]
• Common adverse reactions / dizziness 3% vs 2%; upper respiratory infection 8% vs 7%; nasal congestion 2% vs 1%; back pain 2% vs 1% [1]

Why people stop losartan

In hypertension trials, adverse reactions in at least 2% of losartan patients and more common than with placebo were dizziness (3% vs 2%), upper respiratory infection (8% vs 7%), nasal congestion (2% vs 1%) and back pain (2% vs 1%); discontinuation for adverse events was 2.3% with losartan and 3.7% with placebo [1]. In RENAAL (1513 patients with type 2 diabetic nephropathy), asthenia/fatigue, hypotension, orthostatic hypotension and hyperkalemia were among events reported in at least 4% of losartan patients and at least 2 percentage points more than with placebo [1]. These are trial rates, not a ranking of patient regret.

What the label says about stopping

The boxed warning says to discontinue losartan as soon as pregnancy is detected [1]. Hypersensitivity to any component and coadministration with aliskiren in patients with diabetes are contraindications [1]. For hyperkalemia, the label says to monitor serum potassium and that dose reduction or discontinuation may be required [1]. It warns that renal function can deteriorate, including acute renal failure, in people whose kidney function depends on the renin-angiotensin system, such as those with renal artery stenosis, chronic kidney disease, severe heart failure or volume depletion, and says to monitor renal function and to consider withholding or discontinuing therapy if a clinically significant decrease in renal function develops [1]. Angioedema, including airway swelling, is listed in postmarketing experience; the label says frequency cannot be reliably estimated from voluntary reports [1].

What happens after stopping?

The label's dosing, warnings and adverse-reaction sections do not give blood pressure data or a withdrawal description for the period after stopping losartan [1]. The label describes AT1 receptor blockade by losartan and its active metabolite while the drug is taken [1].

Restarting: what dosing information exists

The label gives no tested schedule for restarting losartan after a break. For adult hypertension it lists a usual starting dose of 50 mg once daily, 25 mg once daily with possible intravascular depletion or mild-to-moderate hepatic impairment, and a maximum of 100 mg once daily [1]. For diabetic nephropathy, it gives 50 mg once daily, increased to 100 mg once daily if needed for blood pressure [1]. These are labeled starting-dose instructions, not a restart plan.

Frequently asked questions

›What happens if I stop losartan suddenly?

The label's dosing, warnings and adverse-reaction sections give no blood-pressure timeline or withdrawal description for stopping losartan. They do name situations where discontinuation is directed or may be needed: pregnancy detected, hyperkalemia, and a clinically significant decrease in renal function [1].

›Can I restart losartan after a break?

The label does not provide a tested schedule for restarting losartan after a break. It lists 50 mg once daily as the usual adult hypertension starting dose, or 25 mg once daily for possible intravascular depletion or mild-to-moderate hepatic impairment; these are labeled starting-dose instructions, not a restart plan [1].

›Does losartan cause the cough ACE inhibitors cause?

In two label cough trials in people with prior ACE-inhibitor cough, cough occurred in 17% on losartan vs 25% on hydrochlorothiazide vs 69% on lisinopril, and 29% on losartan vs 35% on placebo vs 62% on lisinopril [1].

›What is the maximum dose of losartan?

For hypertension the labeled maximum is 100 mg once daily [1]. In HEAAL, a trial in heart failure patients intolerant of ACE inhibitors, 150 mg daily caused more renal impairment, hypotension and hyperkalemia than 50 mg [2].

References

1. U.S. National Library of Medicine, DailyMed. Losartan Potassium prescribing information. Losartan Potassium label
2. Konstam MA, Neaton JD, Dickstein K, Drexler H, Komajda M, Martinez FA, et al. Effects of high-dose versus low-dose losartan on clinical outcomes in patients with heart failure (HEAAL study): a randomised, double-blind trial. Lancet. 2009;374(9704):1840-8. Effects of high-dose versus low-dose losartan on clinical outcomes in patients with heart failure (HEAAL study): a randomised, double-blind trial