Pharmaniaga Fentanyl Overdosage

Symptoms: Overdosage of fentanyl expresses itself by prolongation of the duration of the pharmacological effects. Dependent on the individual sensitiveness, the clinical picture is respiratory depression ranging from bradypnoea to apnoea, bradycardia up to asystole, decrease in blood pressure, circulatory failure, coma, seizure-like activity, muscle rigidity of the chest wall, trunk and extremities, and pulmonary oedema.
Treatment of overdose: Hypoventilation should be treated by administration of oxygen and the patient should be ventilated. Respiratory depression should be treated by administration of an opioid antagonist like naloxone. The usual initial naloxone dose amounts 0.4 to 2 mg. If no effect can be seen, this dose may be repeated every 2 to 3 minutes up to reversal of respiratory depression or awakening. Since the respiratory depressant effect of fentanyl may last longer than the antagonistic effect, repeated doses of naloxone may be appropriate.
Ventilatory problems caused by muscle rigidity can be diminished or abolished by application of a peripherally acting muscle relaxant. The patient should be monitored carefully. Normal body temperature and balanced fluid volumes should be ensured.
In the case of severe and persistent hypotension, hypovolaemia should be considered, which can be compensated by parenteral fluid therapy.