Objectives: Resistance to antiepileptic drugs has occurres in some patients. The aim of this study was to evaluate the patients with refractory partial epilepsy who initially responded to levetiracetam (LEV) add-on therapy and who had the seizure frequency return to their baseline after a honeymoon period. Methods: Seven patients with refractory epilepsy, who had transient seizure control with LEV add-on therapy, were included in this study. Age, sex, detailed medical history, epilepsy duration, seizure frequency, concomitant AEDs, time to seizure occurrence after the initiation of LEV, side effects of LEV, cranial magnetic resonance imaging (MRI) and electroencephalography (EEG) data were collected for each patient. Results: Mean age was 26.14±5.14 years. Three patients were male and the other four were female. Mean seizure frequency before LEV treatment was 8.71±5.25 /month. The seizure-free days with levetiracetam add-on therapy was 51-82 days. After the honeymoon effect, seizure frequency returned to the baseline level and did not changed despite an increase in dosage. Cranial MRI was normal in two patients, while interictal EEG was normal in two patients. Conclusion: The resistance to LEV add-on treatment in patients with refractory partial onset seizures may develop, but the honeymoon effect of LEV was longer in our patients when compared to the drug’s literature.