A Case Report on Pregabalin-Induced Eosinophilia.

This is a case report on a 77-year-old diabetic patient with peripheral neuropathy and paresthesias in his feet, for which he was treated with pregabalin. During the therapy, his eosinophil level was high (60.3%). Pregabalin was stopped, and after one month his differential eosinophil had dropped dramatically, to 7.3%. Based on the Naranjo Adverse Drug Reaction scale, it is probable that the eosinophilia was induced by pregabalin, as the Naranjo probability score was calculated to be 8.

BACKGROUND

Pregabalin, a structural derivative of the inhibitory neurotransmitter gamma amino butyric acid, has antiepileptic, analgesic, and anxiolytic properties; therefore, it is used for painful diabetic neuropathy, postherpetic neuralgia, fibromyalgia, and neuropathic pain associated with spinal-cord injury and as adjunctive therapy in refractory partial seizures. The common adverse side effects include somnolence, weight gain, dizziness, peripheral edema, abnormal constipation, thirst, and blurring of vision.

METHODS

This is a case report on a 77-year-old diabetic patient with peripheral neuropathy and paresthesias in his feet (with a nocturnal preponderance), for which he was treated with pregabalin. During the pregabalin therapy, his eosinophil level was high (60.3%). Pregabalin was stopped, and after one month his differential eosinophil had dropped dramatically, to 7.3%. Based on the Naranjo Adverse Drug Reaction scale, it is probable that the eosinophilia was induced by pregabalin, as the Naranjo probability score was calculated to be 8.

CONCLUSIONS

The incidence of eosinophilia attributable to pregabalin is very rare and warranted discontinuation of the drug.