A 26-year old tetraplegic male patient with C8 AIS-D (American impairment scale) lesion admitted to our clinic for rehabilitation. He had Grade 3 spasticity in his lower limbs according to Modified Ashworth scale and Grade 1 spasticity in his upper limbs. Although he was able to walk without any assistance, plantar flexor spasticity in his right ankle was limiting his dorsiflexion and was causing a gait disorder. He was given baclofen 10 mg/day for spasticity and the dose increased gradually according to the response. When the baclofen dose reached 70 mg/day, the patient reported visual hallucinations. After the reduction of the baclofen dose to 60 mg/day, the hallucinations disappeared.