Losartan and Hydrochlorothiazide

Angiotensin-II Antagonist · Angiotensin II antagonist/Thiazide diuretic

Indications

Hypertension in patients stabilized on losartan and hydrochlorothiazide given separately in the same proportion.

Dosage

Adults: Initially 1 tab daily. Increased to max 100 mg losartan daily if necessary. Children: Not recommended.

Adverse Effects

Dizziness, orthostatic effects, diarrhoea, liver function abnormalities, myalgia, migraine, urticaria, pruritus, rash. Rarely, anaphylactic reactions, angioedema, vasculitis, hepatitis, cough, anaemia, asthaenia, fatigue, musculoskeletal or chest pain, hypotension, electrolyte disturbances, hypoglycaemia, headache, insomnia, GI upset, cough, upper RTI, renal impairment, reduced haematocrit or haemoglobin.

Risk Factor (Pregnancy/Lactation)

Pregnancy: Contraindicated in pregnancy. Lactation: Contraindicated or not recommended. Contraindications: Hepatic impairment. Anuria, moderate to severe renal impairment, dialysis, cholestasis, biliary obstruction, primary aldosteronism. Refractory hypokalaemia, hypercalcaemia or hyponatraemia, hyperuricaemia, gout. Precautions: History of angioedema. renal impairment, intravascular volume depletion, renal artery stenosis, kidney transplantation, severe heart failure, arrhythmias, obstructive valvular disease, aortic stenosis, obstructive hypertrophic cardiomyopathy, SLE, asthma. Monitor serum potassium in the elderly and in renal impairment. Diabetes; monitor serum electrolytes, creatinine and uric acid.

Interactions

Barbiturates, narcotics, antidiabetic agents, cholestyramine, colestipol, corticosteroids, ACTH, adrenaline, muscle relaxants, lithium, NSAIDs, K+-sparing diuretics, K+ suppl, other antihypertensives, aspirin, hypoglycaemics, alcohol, CNS depressants, antidepressants, laxatives, amphotericin, sympathomimetics, uricosuric agents, allopurinol, anticholinergics, cytotoxics, cyclosporin, digoxin, other drugs affected by serum K+ disturbances, methyldopa, calcium suppl, iodinated contrast media, rifampicin, fluconazole.

Advice to Patient

Take with or without meals. Do not take within 4 hours of bedtime. Contact prescriber if there is any allergic reaction (rash, hives, itching, difficulty in breathing, swelling on face/lips/tongue/throat), fast/slow/irregular heartbeat, confusion, severe dizziness. If you also take cholesterol lowering medications, take this medication atleast 4 hours before or 4-6 hours after cholesterol lowering medications. Reduce alcohol intake. Take sufficient amount of fluids (2-3 litres per day) to maintain hydration, unless restricted by the prescriber. Check blood sugar levels and blood pressure regularly and inform prescriber about changes. Certain blood tests are required during treatment, keep all doctors and lab appointments. Avoid direct sunlight, tanning booths and sunlamps. Wear sunscreen, eyewear and protective clothing to prevent photosensitivity.

Pharmacokinetics

LOSARTAN: Onset of action: Approx. 6 hrs. Absorption: Well absorbed; slowed with food. Metabolism: Hepatic. Bioavailability: Approx. 33%. Half-life elimination: Losartan: Children 6-16 yrs: 2.3 ± 0.8 hrs. Adults: 2.1 ± 0.7 hrs. E-3174 (active metabolite): Children 6-16 yrs: 5.6 ± 1.2 hrs. Adults: 7.4 ± 2.4 hrs. Time to peak, serum: Losartan: Children: 2 hrs. Adults: 1 hr. E-3174 (active metabolite): Children: 4.1 hrs. Adults: 3.5 hrs. Excretion: Urine (35%). Faeces (Approx. 60%). HYDROCHLOROTHIAZIDE: Onset of action: Diuresis: Infants: 2-6 hrs. Adults: Approx. 2 hrs. Peak effect: 4-6 hrs. Duration: Infants: 8 hrs. Adults: 6-12 hrs. Absorption: Well absorbed, absorption is decreased in patients with CHF. Metabolism: Not metabolized. Bioavailability: 65%-75%. Half-life elimination: Approx. 6-15 hrs. Time to peak: Approx. 1-5 hrs. Excretion: Urine.

Compiled by Healify Pharmacy from published drug references. How we compile it →

Always consult a pharmacist or doctor.