Home › Compound Library › Losartan (Cozaar)

Losartan (Cozaar)

ARBprescriptionoral · inferred

Angiotensin II receptor blocker (ARB) for hypertension, diabetic nephropathy, and stroke prevention. Prodrug converted to active metabolite EXP3174 via CYP2C9/CYP3A4; EXP3174 is 10-40x more potent than losartan with a longer half-life. Also has uricosuric properties.

Projected serum levels — 50 mg, once daily

Losartan (Cozaar)
Losartan (Cozaar) modeled serum levels, 50 mg once daily over 15 days Population-based pharmacokinetic estimate. Steady state reached after approximately 1 days. 0 2.5 5 7.5 10 Day 0 Day 4 Day 8 Day 11 Day 15 Time on a regular schedule ≈ steady state · day 1

Maintenance schedule: 50 mg once daily (oral).

Modeled steady state after ~1 days: peak ≈ 6.7 mg, trough ≈ 0.000 mg body load. Population-based estimate over 15 days for a 50 mg dose at a 70 kg reference body mass — the interactive app scales curves to your doses, timing, and body mass.

Key facts

Category
ARB
Route modeled
Oral
Model confidence
inferred
Half-life
2.1 h
Common dose
50 mg
Suggested maximum
100 mg/day
Reference dose range
25–100 mg (single dose)
Suggested cadence
once daily
Validated against
50 mg oral — Cmax 0.22 mg/L at 1 h

Documented interactions

  • danger
    Carbamazepine (Tegretol) + Losartan (Cozaar) CYP induction

    Carbamazepine (Tegretol) inducer of CYP3A4 predicted to change Losartan (Cozaar) AUC by ~0.40x

  • danger
    Efavirenz (Sustiva) + Losartan (Cozaar) CYP induction

    Efavirenz (Sustiva) inducer of CYP3A4 predicted to change Losartan (Cozaar) AUC by ~0.28x

  • danger
    Levothyroxine (Synthroid) + Losartan (Cozaar) Protein binding

    Losartan (Cozaar) may displace Levothyroxine (Synthroid) from plasma protein binding sites, transiently raising free drug concentration. This drug has a narrow therapeutic index; free concentration…

  • danger
    Rifampin + Losartan (Cozaar) CYP induction

    Rifampin inducer of CYP3A4 predicted to change Losartan (Cozaar) AUC by ~0.28x

  • danger
    St. John's Wort (Hypericum perforatum) + Losartan (Cozaar) CYP induction

    St. John's Wort (Hypericum perforatum) inducer of CYP3A4 predicted to change Losartan (Cozaar) AUC by ~0.47x

  • danger
    Tacrolimus (Prograf) + Losartan (Cozaar) Protein binding

    Losartan (Cozaar) may displace Tacrolimus (Prograf) from plasma protein binding sites, transiently raising free drug concentration. This drug has a narrow therapeutic index; free concentration…

Serum checks 217 modeled interaction pairings for losartan (cozaar) across your whole stack — absorption conflicts, enzyme inhibition, and nutrient depletion included.

Research behind this entry

  1. Cardiovascular morbidity and mortality in the Losartan Intervention For Endpoint reduction in hypertension study (LIFE): a randomised trial against atenolol Dahlof B et al. · Lancet, 2002 DOI

    Landmark LIFE trial of 9,193 hypertensive patients with LVH found losartan-based therapy reduced the primary composite endpoint by 13% and stroke by 25% compared to atenolol-based therapy.

  2. Effects of losartan on renal and cardiovascular outcomes in patients with type 2 diabetes and nephropathy (RENAAL) Brenner BM et al. · New England Journal of Medicine, 2001 DOI

    RENAAL trial of 1,513 patients demonstrated losartan reduced the risk of doubling of serum creatinine by 25% and end-stage renal disease by 28% in type 2 diabetic nephropathy.

  3. Pharmacokinetics of losartan, an angiotensin II receptor antagonist, and its active metabolite EXP3174 in humans Lo MW et al. · Clinical Pharmacology & Therapeutics, 1995 DOI

    Definitive PK study establishing losartan half-life of 2.1h, EXP3174 half-life of 6.3h, and approximately 14% conversion of losartan to the 10-40x more potent active metabolite.

3 published studies referenced in the app, each with a plain-language summary.