[Carbamazepine poisoning caused by confusing the drugs].
METHODS
By error a pharmacist had dispensed to a 41-year-old woman Tegretal (carbamazepine; 400 mg retard tablets) instead of Trental (pentoxifylline; 400 mg retard dragées). Similarly, a 76-year-old woman had been prescribed carbamazepine-neuroxpharm (600 mg retard tablets) instead of piracetam-neuraxpharm (800 mg tablets) by her family doctor. Thirdly, a 79-year-old man was, as an in-patient, by error given by a nurse Tegretal, 400 mg retard tablets three times daily, presumably instead of 400 mg Trental retard. All 3 patients developed mild cerebellar symptoms. The two elder patients showed additionally wakefulness. After a fall the male in-patient, known to have a hemiparesis, also developed myoclonus in the limbs: computed tomography demonstrated a mild left temporal contusion.


METHODS
Routine laboratory tests were unremarkable. All 3 patients had raised carbamazepine levels (12-13 micrograms/ml [normal range: 4-12 micrograms/ml]).


METHODS
Because fast carbamazepine saturation had been done in those three patients by error, all of them showed symptoms of carbamazepine overdosage, but all symptoms fully regressed within a few days without specific treatment.


CONCLUSIONS
Adverse drug events are not rare in routine medical practice and should be thought of in the differential diagnosis of both in- and out-patients with unclear symptoms. In addition to careful history-taking and consideration of the clinical symptoms, toxicological screening can be of vital importance.
Rösel
T
T
Neurologische Klinik, Städtischen Klinikums Karlsruhe.
Schneider
J
J
Fischer
J T
JT
Druschky
K F
KF
D000328:Adult; D000368:Aged; D000927:Anticonvulsants / Q000009:adverse effects* / Q000627:therapeutic use; D002220:Carbamazepine / Q000009:adverse effects* / Q000627:therapeutic use; D002544:Cerebral Infarction / Q000188:drug therapy; D003937:Diagnosis, Differential; D062787:Drug Overdose; D005260:Female; D006311:Hearing Disorders / Q000188:drug therapy; D006401:Hematologic Agents / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008508:Medication Errors; D018696:Neuroprotective Agents / Q000627:therapeutic use; D010291:Paresis / Q000188:drug therapy; D010431:Pentoxifylline / Q000627:therapeutic use; D010889:Piracetam / Q000627:therapeutic use
D000927:Anticonvulsants; D006401:Hematologic Agents; D018696:Neuroprotective Agents; D002220:Carbamazepine; D010431:Pentoxifylline; D010889:Piracetam