Citation

Mercan A, Karabiyik L. Anestezi Dergisi 2023; 31: 142-144.

Copyright

(Copyright © 2023, Anesteziyoloji ve Reanimasyon Uzmanları Derneği)

DOI

unavailable

PMID

unavailable

Abstract

BACKGROUND: Phenytoin is a commonly prescribed antiepileptic drug. The narrow therapeutic index, the wide individual variability in the rate of Phenytoin metabolism and clearance are responsible from the observed dose-related toxicity. Parenteral form of Phenytoin contains propylene glycol as an excipient. In case of acute intoxication; agitation and restlessness, drowsiness, lethargy, increased reflexes, stupor and coma, respiratory arrest, hypotension, bradycardia and delusions are observed. In this case, we aimed to present the prolonged Phenytoin fluctuation in drug level after iatrogenic Phenytoin intoxication in a patient who received propylene glycol from Phenytoin ampule and polyethylene glycol for colonoscopy preparation. Case: A 72-year-old male patient applied to the emergency service after having multiple seizures. He had a seizure after applying polyethylene glycol for colonoscopic preparation. Phenytoin was loaded to stop the seizures. After Phenytoin, the patient developed confusion, hyperactivity and agitation. The patient with a blood Phenytoin level of 50 microgram/mL was admitted to the intensive care unit with the diagnosis of Phenytoin intoxication. Since there was no specific antidote for Phenytoin toxicity, symptomatic treatment was applied. The patient with high troponin level was followed-up in terms of cardiac side effects. Liver enzymes were elevated. Daily blood Phenytoin level was monitored. After the first four days, neurological examination did not regress and seizure did not develop. The patient, whose blood Phenytoin level was fluctuating and did not fall to the normal therapeutic value, was applied to hemodialysis on the 7th day. The patient was transferred to the geriatric service on the 9th day of hospitalization, as his cardiac status remained stable and the drug level fell below the normal value.

DISCUSSION: The serum level at which the toxic effect of Phenytoin begins is >20 microgram/mL. Phenytoin can also cause myocardial damage by rapid administration of parenteral forms containing propylene glycol as a solvent. In addition, the patient's age, comorbidities and polypharmacy increase the risk of side effects and the tendency to intoxication.

CONCLUSION: In addition, propylene glycol in ampoules as excipients and polyethylene glycol taken in preparation for colonoscopy may have contributed to the intoxication clinic.

Language: en