Bradycardia and hypotension associated with fomepizole infusion during hemodialysis.
We report a case of hypotension and bradycardia associated with intravenous fomepizole infusion.


METHODS
A 59-year-old man presented to hospital 10 hours after ethylene glycol ingestion with ataxia, slurred speech, metabolic acidosis, heart rate 70/min, blood pressure 160/100 mmHg. Treatment with hemodialysis and fomepizole began 7.5 hours after admission. Severe bradycardia (29/min) and hypotension (69 mmHg systolic) occurred immediately following a 30 minute intravenous infusion of the first (19 mg/kg) fomepizole dose, but rapidly corrected with 1 mg atropine. Transient bradycardia (48/min) and hypotension (89/57 mmHg) recurred immediately after the second (10 mg/kg) fomepizole dose, also given during dialysis.


CONCLUSIONS
Hemodialysis may cause a drop in blood pressure and heart rate; however, the close temporal relationship with fomepizole infusions, dose-related symptom intensity and recurrence with rechallenge suggest a causal relationship with fomepizole. Hemodialysis, acidosis and high initial fomepizole dose may have enhanced patient susceptibility, as a post-dialysis fomepizole dose was well tolerated.


CONCLUSIONS
Fomepizole may precipitate bradycardia and/or hypotension during hemodialysis. Monitor vital signs closely during and immediately after infusion.
Lepik
Katherine J
KJ
BC Drug & Poison Information Centre, Vancouver, British Columbia, Canada. lepik@interchange.ubc.ca
Brubacher
Jeffrey R
JR
DeWitt
Christopher R
CR
Lam
George S S
GS
Lawson
Edward J
EJ
Erhardt
Gunnar D
GD
Purssell
Roy A
RA
Kennedy
James R
JR
Brignall
Jane L
JL
D000138:Acidosis / Q000150:complications; D000931:Antidotes / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects; D001919:Bradycardia / Q000139:chemically induced; D004305:Dose-Response Relationship, Drug; D019855:Ethylene Glycol / Q000506:poisoning; D000077604:Fomepizole; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007022:Hypotension / Q000139:chemically induced; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D011720:Pyrazoles / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D006435:Renal Dialysis
D000931:Antidotes; D011720:Pyrazoles; D000077604:Fomepizole; D019855:Ethylene Glycol