Formulary
Losartan potassium: Indications, Dosing, Side Effects and Interactions
Losartan potassium clinical drug profile including indications, dosing, side effects, cautions and interactions.
MedNext Academy | 4 min read
Losartan potassium: Indications, Dosing, Side Effects and Interactions
Losartan potassium clinical drug profile including indications, dosing, side effects, cautions and interactions.
Indications and dose
**Diabetic nephropathy in type 2 diabetes mellitus**
- **Adult** (By Mouth): 76 years and over Initially 25 mg once daily for several weeks, then increased if necessary up to 100 mg once daily.
**Chronic heart failure when ACE inhibitors are unsuitable or contra-indicated**
- **Adult** (By Mouth): Initially 12.5 mg once daily, increased if tolerated to up to 150 mg once daily, doses to be increased at weekly intervals.
**Hypertension (including reduction of stroke risk in hypertension with left ventricular hypertrophy)**
- **Adult** (By Mouth): 76 years and over Initially 25 mg once daily for several weeks, then increased if necessary up to 100 mg once daily.
**Hypertension with intravascular volume depletion**
- **Adult** (By Mouth): 18-75 years Initially 25 mg once daily for several weeks, then increased if necessary up to 100 mg once daily.
**Hypertension for losartan potassium**
- **Child 6-17 years (under expert supervision) (body-weight 20-49 kg)** (By mouth): Initially 700 micrograms/kg once daily (max. per dose 25 mg), lower initial dose may be used in intravascular volume depletion, adjusted according to response to 50 mg once daily.
- **Child 6-17 years (under expert supervision) (body-weight 50 kg and above)** (By mouth): Initially 50 mg once daily, adjusted according to response to 1.4 mg/kg once daily (max. per dose 100 mg).
**Hypertension with intravascular volume depletion for losartan potassium**
- **Child 6-17 years (under expert supervision) (body-weight 50 kg and above)** (By mouth): Initially 25 mg once daily; adjusted according to response to up to 1.4 mg/kg once daily (max. per dose 100 mg).
Cautions
II receptor antagonists Aortic or mitral valve stenosis; elderly (lower initial doses may be appropriate); hypertrophic cardiomyopathy; patients of black African or African-Caribbean origin; patients with a history of angioedema; patients with primary aldosteronism (may not benefit from an angiotensin-II receptor antagonist); renal artery stenosis Cautions, further information Elderly Screening Tool of Older Persons' potentially inappropriate Prescriptions (STOPP) criteria to aid medication reviews (see Prescribing in the elderly for information). Potentially inappropriate: with hyperkalaemia with persistent postural hypotension i.e. recurrent drop in systolic blood pressure 20 mmHg (risk of syncope and falls) Cautions For losartan potassium Severe heart failure
Contraindications
II receptor antagonists The combination of an angiotensin-II receptor antagonist with aliskiren is contra-indicated in patients with an eGFR less than 60 mL/minute/1.73 m 2 ; the combination of an angiotensin-II receptor antagonist with aliskiren is contra-indicated in patients with diabetes mellitus
Side effects
II receptor antagonists Common or very common Abdominal pain; asthenia; back pain; cough; diarrhoea; dizziness; headache; hyperkalaemia; hypotension; nausea; postural hypotension (more common in patients with intravascular volume depletion, e.g. those taking high-dose diuretics); renal impairment; vertigo; vomiting Uncommon Angioedema; myalgia; skin reactions; thrombocytopenia Rare or very rare Arthralgia; hepatic function abnormal Side-effects For losartan potassium Common or very common Anaemia; hypoglycaemia; postural disorders Uncommon Angina pectoris; constipation; drowsiness; dyspnoea; oedema; palpitations; sleep disorder Rare or very rare Atrial fibrillation; hepatitis; hypersensitivity; paraesthesia; stroke; syncope; vasculitis Frequency not known Depression; erectile dysfunction; hyponatraemia; influenza like illness; malaise; migraine; pancreatitis; photosensitivity reaction; rhabdomyolysis; taste altered; tinnitus; urinary tract infection
Interactions
**Other interactions (28):**
- Losartan Rifampicin and fluconazole have been reported to reduce levels of active metabolite.
- As with other drugs that block angiotensin II or its effects, concomitant use of potassium-sparing diuretics (e.g.
- As with other medicines which affect the excretion of sodium, lithium excretion may be reduced.
- Therefore, serum lithium levels should be monitored carefully if lithium salts are to be co-administered with angiotensin II receptor antagonists.
- Concomitant use of angiotensin II antagonists or diuretics and NSAIDs may lead to an increased risk of worsening of renal function, including possible acute renal failure, and an increase in serum...
- Clinical trial data have shown that dual blockade of the renin-angiotensin-aldosterone system (RAAS) through the combined use of ACE-inhibitors, angiotensin II receptor blockers or aliskiren is...
Pregnancy
Important safety information For all angiotensin II receptor antagonists MHRA/CHM advice: ACE inhibitors and angiotensin II receptor antagonists: not for use in pregnancy (December 2014) See Conception and contraception and Pregnancy . MHRA/CHM advice: ACE inhibitors and angiotensin II receptor antagonists: recommendations on how to use for breastfeeding (December 2014) See Breast feeding .
Breast feeding
II receptor antagonists Information on the use of angiotensin-II receptor antagonists in breast-feeding is limited. They are not recommended in breast-feeding. Alternative treatment options, with better established safety profile during breast-feeding, are preferable M (recommendation also supported by specialist sources).
Hepatic impairment
II receptor antagonists In general, manufacturers advise caution in mild to moderate impairment (limited information available); avoid in severe impairment (no information available). Hepatic impairment For losartan potassium Dose adjustments Manufacturer advises consider dose reduction if history of impairment (risk of increased plasma concentrations).
Renal impairment
II receptor antagonists Dose adjustments In general, manufacturers advise start with low dose and adjust according to response.
Medicinal forms
Solution
Clinical governance
**Author:** MedNext Clinical Team. **Clinical reviewer:** Dr Shameer Deen, MBBS, MS, MRCS. **Sources:** BNF, Indian Pharmacopoeia, CIMS India. **Correction:** Report errors at support@mednext.academy.
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