3. M
edical Toxicology
and
Drug
Abuse
Research
Center
Dr.Om
id
M
ehrpour
Acute ingestion
For acute ingestions, no evidence of bleeding on the initial clinical
Examination.
Obtain a baseline PT/INR (repeat measurement in 24-48Hours)
activated charcoal (Gastric lavage is unnecessary if rapid
administration of activated charcoal is feasible. Do not induce
emesis.)
Do not administer vitamin K1 prophylactically.
Elevated PT : vitamin K1(Ten milligrams orally daily) for more
than several days.
Superwarfarin induced coagulopathies, 50-200 mg daily is
recommended many weeks.
4. M
edical Toxicology
and
Drug
Abuse
Research
Center
Dr.Om
id
M
ehrpour
Chronic intoxication
the INR is higher than therapeutic levels but less
than 5 and the patient is not bleeding:
withhold warfarin for 2-3days (restart when the INR
approaches the therapeutic range)
If the patient requires more rapid reversal (elective
surgery) : 12.5mg of vitamin K1 orally ( the INR will
begin to fall within 8 hours, with a maximal effect in
about 24hours).
5. M
edical Toxicology
and
Drug
Abuse
Research
Center
Dr.Om
id
M
ehrpour
Chronic intoxication
If the INR is higher than 5 but less than 9 and the patient is
not actively bleeding:
withhold warfarin for the next 1 or 2 doses, monitor the INR
more frequently (resume therapy at a lower dose when the
INR is at the therapeutic level)
Another therapeutic approach would be
withhold 1 dose of warfarin
orally administer vitamin K1, 1-2.5mg,
if the patient is at increased risk of bleeding. For more rapid
reversal (urgent surgery) : vitamin K1, 2.5-5 mg, orally