Composition Ramipril 2.5 , 5mg tablets and hydrochlorothiazide 12.5mg tablets
Indication Essential hypertension
Mechanism of Action

Ramipril is a long-acting ACE inhibitor which is metabolised into the active metabolite ramiprilat. Supine and standing blood pressures (BP) are reduced witho reflex tachycardia. Ventricular hypertrophy is reversed and renal blood flow increased. In CHF (CHF), pulmonary artery pressure and pulmonary capillary wedge pressure are reduced. Cardiac function is improved.

Hydrochlorothiazide is a thiazide diuretic. It increases excretion of Na and chloride in approxequiv amounts. Natriuresis may be accompanied by some loss of K and bicarbonate. The rationale behind this combination is that these have a synergistic effect in lowering BP and offer an advantage of once-daily dosing convenience.


Onset: 1-2 hr.

Duration: 24 hr.

Absorption: Well absorbed from the GI tract (50-60%).

Bioavailability: 28% (ramipril); 44% (ramiprilat). Time to peak plasma concentration: 2-4 hr (ramiprilat).

Distribution: Plasma protein binding: Approx 56% (ramiprilat); 73% (ramipril).

Metabolism: Undergoes enzymatic saponification by esterases to form ramiprilat (active metabolite).

Excretion: Mainly via urine (60%, as ramiprilat); faeces (approx 40%). Elimination half-life: 13-17 hr (ramiprilat).

Side effects

Pancreatitis, jaundice, diarrhoea, nausea, vomiting, cramps, constipation, gastric irritation, anorexia, aplastic anaemia, agranulocytosis, leukopaenia, haemolytic anaemia, thrombocytopaenia, vasculitis, resp distress, including pneumonitis and pulmonary oedema, photosensitivity, fever, urticaria, rash, hyperglycaemia, glycosuria, hyperuricaemia, muscle spasm, vertigo, paraesthesias, dizziness, headache, restlessness, renal failure, renal dysfunction, interstitial nephritis, erythema multiforme including Stevens-Johnson syndrome, exfoliative dermatitis including toxic epidermal necrolysis, alopoecia, transient blurred vision, xanthopsia, impotence, dizziness, fatigue, headache, abdominal pain, cough, rarely symptomatic hypotension, angioneurotic oedema of face, lips, tongue, glottis and larynx, syncope, renal impairment, hypersensitivity reactions.

Potentially Fatal: Anaphylactic reactions, electrolyte imbalance, hypotension.


Severe renal disease, impaired hepatic, allergy or bronchial asthma, systemic lupus erythematosus, acute gout, diabetes mellitus, elderly, collagen vascular diseases, should be discontinued before carrying out tests for parathyroid function. Pregnancy and lactation.


Essential hypertension:

Adult: Per tablet contains ramipril 2.5 mg and hydrochlorthiazide 12.5 mg: 1 tablet daily up to a max of 4 tablets daily.