Gabapentin is typically taken in three daily doses that add up to between 900 mg and 2,400 mg. There is no standard dosage of gabapentin for fibromyalgia because it is an off-label use. Studies investigating the use of gabapentin for fibromyalgia used between 1,200 mg and 2,400 mg total daily dose. The maximum dose of gabapentin for any condition is 5,400 mg daily.