We identified 41 New York City residents who had been hospitalized at least overnight between January 1992 and September 1993 because of a toxic isoniazid (INH) exposure. Review of the available medical charts of 33 patients revealed that median age was 19 years, 27 (82%) were females, and 24 (83%) were taking INH chemoprophylaxis for tuberculosis infection. Twenty-two patients had seizures. Twenty-seven (82%) patients had attempted suicide using INH, and another three patients had intentionally misused INH by making up missed doses at one time. All patients survived. Physicians should be aware of the potential for INH toxicity and should assess their patients' current mental and psychosocial status when prescribing it. INH toxicity should be considered when young patients, particularly females, present with unexplained intractable seizures, and treatment with pyridoxine should be given.

Adolescent↗

PubMedDate not supplied

Serum lidocaine concentrations following subcutaneous administration.

Serum lidocaine concentrations were determined following subcutaneous administration for local anesthesia in the management of lacerations in the emergency room setting. Thirty patients received doses of lidocaine hydrochloride 1% solution ranging from 10 to 300 mg. Venous blood samples were drawn 15, 30, 45, and 60 minutes after lidocaine administration. Serum lidocaine determinations were made using an immunoassay system and verified by gas chromatography. There was no evidence of lidocaine absorption from the subcutaneous injection sites. There were no detectable concentrations of lidocaine in any of the patient blood samples. The absorption characteristics of subcutaneously administered lidocaine appear to be altered in traumatized tissue.

Humans↗