Thenox Overdosage

OVERDOSE AND TREATMENT: As with other anticoagulants, bleeding may occur at any site during enoxaparin therapy. An unexpected decrease in hematocrit or blood pressure may indicate hemorrhage and should prompt evaluation to determine a bleeding site. To largely neutralize the effects of enoxaparin following overdosage, the dose of protamine sulfate is determined by the administered dose of the low molecular weight heparin, the time elapsed since the drug was given and blood coagulation studies.
The dose of protamine sulfate to be given should be equal to that of the administered enoxaparin sodium dose if enoxaparin was administered in the previous 8 hours (i.e., 1 mg of protamine sulfate should be given to neutralize 1 mg of enoxaparin sodium).
If more than 8 hours has elapsed since enoxaparin was administered, an infusion of 0.5 mg of protamine sulfate may be given for each 1 mg of enoxaparin sodium administered. If the activated partial thromboplastin time (aPTT) measured 2 - 4 hours after the first protamine infusion remains prolonged, a second dose of 0.5 mg of protamine sulfate may be given for each 1 mg of enoxaparin sodium administered.
Protamine administration may not be required if more than 12 hours has elapsed since administration of enoxaparin. However, even after higher dosages of protamine sulfate, the aPTT may remain more prolonged than would be the case following treatment of overdosage of conventional heparin since anti-Xa activity is never completely neutralized. A maximum of about 60% of anti-Xa activity is neutralized with protamine sulfate administration of overdosage of enoxaparin.