Phenytoin Toxicity from Cocaine Adulteration
In Houston, Texas, a 26-year-old male drug smuggler who swallowed several rocks of crack cocaine to conceal evidence while being apprehended by police was taken to our emergency department (ED) for medical clearance. Initially, he was asymptomatic, and his vital signs and physical exam were normal. After 2 hours of observation, he manifested clinical signs of cocaine toxicity including anxiety, pallor, diaphoresis, agitation, tachycardia, and hypertension. His vital signs changed; his blood pressure was 190/110 mmHg, heart rate 120 bpm, respiratory rate 22 breaths per minute, and temperature 99.6 F. His physical exam was otherwise unchanged. He was given intravenous benzodiazepine boluses and was admitted to a medical intensive care unit. Subsequently he developed confusion, truncal ataxia, diplopia, slurred speech, and multidirectional nystagmus; these changes were not explained by his pharmacological management. Additional examinations, including computer tomography of the brain, diagnostic lumbar puncture and extensive blood testing, were negative for any abnormalities. A neurology consult revealed uncertain diagnosis. A PHT level was obtained at the recommendation of the poison control center. The patient’s PHT level was 48 mcg/mL (therapeutic range: 10 to 20 mcg/mL). The patient had no history of seizures or records of prescribed PHT. Supportive care was continued, and eventually the patient was discharged with no further complaints 72 hours after MICU admission. To challenge the uniqueness of the use of PHT as cocaine adulterant a random blood screen of PHT levels was performed in 10 patients presenting with complaints related to cocaine use to an academic ED in New York City (7 were seen for chest pain, 1 for suicidal ideation, 1 for new-onset seizures, and 1 for headache associated with uncontrolled hypertension). One patient with chest pain had a PHT level of 4 mcg/mL. The patient presenting with headache had a level of 5 mcg/mL. None of the patients screened had any history of seizure disorders or medical indications for the use of PHT. The patients with positive screening tests were unaware of cocaine adulteration.