enalapril maleate + hydrochlorothiazide: clinical use

Prescribing considerations

• Use only after inadequate control with enalapril alone or as replacement for separately stabilised components; it is unsuitable for initial therapy.
• Assess volume status and risks from vomiting, diarrhoea, dietary sodium restriction or other diuretics.
• Review renal function; the fixed formulation may be unsuitable when individual component titration is needed.
• Consider hydrochlorothiazide-associated photosensitivity and cumulative non-melanoma skin-cancer risk.
• Review diabetes, gout, hepatic disease, systemic lupus erythematosus, valvular outflow obstruction and medicines affecting electrolytes or renal function.

Contraindications and cautions

• Hypersensitivity to either active substance, an excipient or sulfonamide-derived medicines
• Severe renal impairment or anuria
• Previous ACE-inhibitor-associated angioedema, or hereditary or idiopathic angioedema
• Concomitant sacubitril/valsartan
• Second or third trimester of pregnancy
• Severe hepatic impairment
• Aliskiren-containing treatment in patients with diabetes or qualifying renal impairment

Monitoring

• Check blood pressure, renal function, sodium and potassium before treatment, after initiation or changes, and periodically according to clinical risk.
• Repeat assessment during acute illness, dehydration or suspected renal deterioration.
• Consider glucose, uric acid, blood counts and lithium monitoring where relevant.
• Investigate suspicious skin or lip lesions and acute ocular symptoms promptly.

Clinical pharmacology

Enalapril is hydrolysed to enalaprilat, which inhibits ACE and lowers angiotensin II and aldosterone activity. Hydrochlorothiazide inhibits sodium reabsorption in the distal renal tubule, increasing sodium and water excretion. Both components depend substantially on renal elimination.

Formulation and product differences

• The selected product is a yellow, capsule-shaped, biconvex scored tablet; the score permits division into equal parts.
• It contains lactose and is essentially sodium-free.
• Safety and efficacy have not been established in people under 18 years.

Tablet

Route: Oral

Strengths: 20 mg + 12.5 mg