| Pentamidine isetionate should be used with particular caution in patients with hepatic and/or renal dysfunction, hypertension or hypotension, hyperglycaemia or hypoglycaemia, leucopenia, thrombocytopenia or anaemia. Fatalities due to severe hypotension, hypoglycaemia, acute pancreatitis and cardiac arrhythmias have been reported in patients treated with pentamidine isetionate, by both the intramusclar and intravenous routes. Baseline blood pressure should be established and patients should receive the drug lying down. Blood pressure should be closely monitored during administration and at regular intervals until treatment is concluded. Therefore patients receiving pentamidine by inhalation should be closely monitored for the development of severe adverse reactions.Pentamidine isetionate may prolong the QT interval. Cardiac arrhythmias indicative of QT prolongation, such as Torsades de Pointes, have been reported in isolated cases with administration of pentamidine isetionate. Therefore, pentamidine isetionate should be used with care in patients with coronary heart disease, a history of ventricular arrhythmias, uncorrected hypokalaemia and or hypomagnesaemia, bradycardia (<50 bpm), or during concomitant administration of pentamidine isetionate with QT prolonging agents.Particular caution is necessary if the QTc exceeds 500 msec whilst receiving pentamidine isetionate therapy, continuous cardiac monitoring should be considered in this case.Should the QTc interval exceed 550 msec then an alternative regimen should be consideredLaboratory monitoring : The following tests should be carried out before, during and after therapy by the parenteral route: | I)
| Blood urea, nitrogen and serum creatinine daily during therapy.
| | II)
| Complete blood and platelet counts daily during therapy.
| | III)
| Fasting blood glucose measurements daily during therapy, and at regular intervals after completion of therapy. Hyperglycaemia and diabetes mellitus, with or without preceding hypoglycaemia have occurred up to several months after cessation of therapy.
| | IV)
| Liver function tests (LFTS) including bilirubin, alkaline phosphatase, aspartate aminotransferase (AST/GOT), and alkaline aminotransferase (ALT/GPT). If baseline measurements are normal and remain so during therapy, test weekly. When there is baseline elevation in LFTS and/or LFTS increase during therapy, continue monitoring weekly unless the patient is on other hepatotoxic agents, when monitoring every 3-5 days is appropriate.
| | V)
| Serum calcium, test weekly. Serum magnesium, test twice weekly.
| | VI)
| Electrocardiograms at regular intervals.
| | VII)
| Urine analysis and serum electrolytes daily during therapy.
| The benefit of aerosolised pentamidine therapy in patients at high risk of a pneumothorax should be weighed against the clinical consequences of such a manifestation. | |