COMPOSITION: Each Hexazide 25 tablet contains 25 mg hydrochlorothiazide.
PHARMACOLOGICAL CLASSIFICATION: A 18.1 Diuretics
PHARMACOLOGICAL ACTION: Hydrochlorothiazide acts both as a diuretic and anti-hypertensive.
It exerts its action by interfering with the distal renal tubular mechanism of electrolyte reabsorption.
It increases the excretion of sodium and chloride, which is accompanied by some loss of potassium, magnesium and bicarbonate.
Urinary calcium excretion is decreased.
Onset of action occurs 2 hours after oral administration and duration of action is approximately 6 to 12 hours.
associated with congestive cardiac failure, hepatic cirrhosis, nephrotic syndrome.
Hydrochlorothiazide may be used alone or in combination with other antihypertensive agents.
CONTRA-INDICATIONS: Severe renal and hepatic dysfunction.
Hypersensitivity to any component of this medicine formulation or other sulphonamide-derived medicines. Safety of use during pregnancy and lactation has not yet been established.
Patients with Addisons disease.
DOSAGE AND DIRECTIONS FOR USE: Therapy should be initiated at the lowest dose required to achieve the desired effect.
Treatment should be individualised. Adults:
Oedema : usual dose is 25 mg to 50 mg per day. When adequate control of oedema has been achieved the patient may be maintained on one tablet per day. In order to minimise excessive response and undesirable electrolyte imbalance, the dose may be administered on alternate days or on three to five days each week.
The maximum recommended daily dose is 100 mg. Hypertension : usual dose is 12,5 mg to 25 mg daily as a single dose. The initial dosage should be 12,5 mg, whether hydrochlorothiazide is used as a single preparation or in combination. Dosage should be adjusted until the desired blood pressure is obtained and maintained. The maximum recommended daily dose is 100 mg.
It may be necessary to decrease the dose of concomitantly administered antihypertensives, in order to avoid an excessive decrease in blood pressure.
SIDE-EFFECTS AND SPECIAL PRECAUTIONS:
Side effects Gastro-intestinal Anorexia, gastric irritation, nausea, vomiting, cramping, diarrhoea, constipation, jaundice (intrahepatic cholestatic jaundice), pancreatitis, sialoadenitis. Central Nervous System Dizziness, vertigo, parasthesia, headache, xanthopsia. Haematologic Leucopenia, agranulocytosis, thrombocytopenia, aplastic anemia, haemolytic anemia. Cardiovascular Orthostatic hypotension (aggravated by barbiturates, alcohol or narcotics). Hypersensitivity Purpura, photosensitivity, rash, urticaria, necrotizing angiitis (vasculitis) (cutaneous vasculitis), fever, respiratory distress including pneumonitis and pulmonary oedema, anaphylactic reactions. Metabolic Hypokalaemia, hyponatraemia, hyperglycaemia, glycosuria, hyperuricaemia, hypomagnesaemia, hypercalcaemia. Renal: Renal dysfunction, interstitial nephritis, renal failure. Others: Muscle spasm, weakness, restlessness, transient blurred vision, impotence, yellow vision, cholestatic jaundice, pancreatitis.
Should side effects be moderate to severe, it is suggested that the dose of hydrochlorothiazide be reduced or that treatment be withdrawn. SPECIAL PRECAUTIONS: Electrolyte imbalance: The patient should be carefully observed for signs and symptoms of electrolyte and fluid imbalance, which include thirst, dryness of mouth, weakness, lethargy, drowsiness, restlessness, muscle pains or cramps, muscular fatigue, oliguria, hypotension, tachycardia and gastrointestinal disturbances such as nausea and vomiting.
It is particularly important to make urine and serum electrolyte determinations when the patient is vomiting excessively or receiving parenteral fluids. Careful check should be kept for signs of hyponatremia, hypochloraemic alkalosis, hypokalaemia and hypomagnesemia.
Hypokalemia may develop with hydrochlorothiazide, especially following brisk diuresis and prolonged therapy, or hepatic cirrhosis and with concomitant ACTH or steroid administration.
Hypokalemia can sensitize or exaggerate the response of the heart to the toxic effects of digitalis.
Diuretic induced hyponatremia may occur.
Since the urinary excretion of calcium is decreased, elevation of serum calcium, in the absence of disorders of calcium metabolism may occur. Hydrochlorothiazide therapy should be withdrawn before carrying out parathyroid function tests.
Elderly patients are particularly susceptible to electrolyte imbalance. Impaired Renal Function and/or Azotaemia: Hydrochlorothiazide treatment is ineffective once creatinine clearance falls below 30 mL/min.
Azoteamia may be precipitated or aggravated by hydrochlorothiazide.
If renal function is impaired, cumulative effects of the drug may be observed.
If increasing azotaemia and oligouria occur, during treatment of severe progressive renal disease, the diuretic should be discontinued. Hepatic disease: Use with caution in patients with impaired hepatic function or progressive liver disease, since minor alterations in fluid or electrolyte balance may precipitate hepatic coma. Metabolic: Hyperuricaemia and/or gout may be precipitated in patients receiving hydrochlorothiazide.
Glucose tolerance is impaired by hydrochlorothiazide, therefore the dosage of antidiabetic agents including insulin may have to be adjusted.
Hydrochlorothiazide may cause hyperglycaemia and aggravate or unmask diabetes mellitus.
Patients with cirrhosis of the liver are particularly at risk from hypokalaemia. Other: Exacerbation or activation of systemic lupus erythematosus and an increase in blood cholesterol have been reported.
Attacks of gout may be precipitated in susceptible patients.
INTERACTIONS The following medicines may interact with hydrochlorothiazide when administered concurrently. Digitalis glycosides - hydrochlorothiazide may enhance the toxicity of these agents, by depleting serum potassium concentrations. Alcohol, barbiturates or narcotics - potentiation of orthostatic hypotension. Antidiabetic agents - (Insulin and oral antidiabetics) Dosage adjustment of the antidiabetic agents may be necessary. Other antihypertensive agents - additive effects. Diuretic therapy should be discontinued for 2 to 3 days prior to initiation of therapy with an ACE inhibitor, to reduce the likelihood of first dose hypotension. Corticosteroids and ACTH - severe electrolyte depletion, especially hypokalaemia. Pressor amines - decreased response to pressor amines (eg. adrenalin) Non depolarising skeletal muscle relaxants (eg. tubocuranine) - increased responsiveness to muscle relaxant. Lithium - hydrochlorothiazide reduces the renal clearance of lithium, thus lithium toxicity may occur. Dosage adjustments of lithium may be necessary. Non steroidal anti-inflammatory agents - reduction of diuretic, natriuretic and anti-hypertensive effects have been reported. Medicine/laboratory test interactions - hydrochlorothiazide interferes with the tests for parathyroid function (see side effects and special precautions).
KNOWN SYMPTOMS OF OVERDOSAGE AND PARTICULARS OF ITS TREATMENT: See side effects and special precautions.
Treatment is symptomatic and supportive.
IDENTIFICATION: White to off-white, round, biplanar tablet with a facette and a cross score notch. diameter: 8,0 +0,2 mm, height: 2,6 +0,2 mm
PRESENTATION: White opaque polypropylene/aluminium blisters.
10 tablets per blister strip.
10 blister strips per carton (100s)
STORAGE INSTRUCTION: Store in tight, well closed containers below 25°C. Protect from moisture.
KEEP OUT OF REACH OF CHILDREN.
REGISTRATION NUMBER: 32/18.1/0419
NAME AND ADDRESS OF THE APPLICANT: HEXAL Pharma (SA) (Pty) Ltd
46 Mahogany Road
DATE OF PUBLICATION OF THIS PACKAGE INSERT: 10 October 2000
Updated on this site: December 2004
Source: Community Pharmacy