l INDICATIONS AND DOSE

Overdosage with intravenous injection of unfractionated heparin

BY INTRAVENOUS INJECTION

Adult: Dose to be administered at a rate not exceeding 5 mg/minute, 1 mg neutralises 80–100 units heparin when given within 15 minutes; if longer than 15 minute since heparin, less protamine required (consult product literature for details) as heparin rapidly excreted; maximum 50 mg Overdosage with intravenous infusion of unfractionated heparin

 BY INTRAVENOUS INJECTION

 Adult: 25–50 mg, to be administered once heparin infusion stopped at a rate not exceeding 5 mg/minute Overdosage with subcutaneous injection of unfractionated heparin

 INITIALLY BY INTRAVENOUS INJECTION

Adult: Initially 25–50 mg, to be administered at a rate not exceeding 5 mg/minute, 1 mg neutralises 100 unit heparin, then (by intravenous infusion), any remaining dose to be administered over 8–16 hours; maximum 50 mg per course Overdosage with subcutaneous injection of low molecular weight heparin

 BY INTRAVENOUS INJECTION, OR BY CONTINUOUS INTRAVENOUS INFUSION

Adult: Dose to be administered by intermittent intravenous injection at a rate not exceeding 5 mg/minute, 1 mg neutralises approx. 100 units low molecular weight heparin (consult product literature of low molecular weight heparin for details); maximum 50 mg 

CAUTIONS

Excessive doses can have an anticoagulant effect

l SIDE-EFFECTS 

Rare or very rare Hypertension . pulmonary oedema noncardiogenic  Frequency not known Acute pulmonary vasoconstriction . back pain . bradycardia . circulatory collapse . dyspnoea . fatigue . feeling hot. flushing . nausea . pulmonary hypertension . vomiting

 ALLERGY AND CROSS-SENSITIVITY

Caution if increased risk of allergic reaction to protamine (includes previous treatment with protamine or protamine insulin, allergy to fish, men who are infertile or who have had a vasectomy and who may have antibodies to protamine).

 MONITORING REQUIREMENTS

Monitor activated partial thromboplastin time or other appropriate blood clotting parameters.

PRESCRIBING AND DISPENSING INFORMATION

The long half-life of low molecular weight heparins should be taken into consideration when determining the dose of protamine sulfate; the effects of low molecular weight heparins can persist for up to  24 hours after administration. l MEDICINAL FORMS