3-6 weeks should determine if the dosage should be increased, to achieve effective symptom control.
Pain control, on the other hand, is usually achieved by a mix of a pain killer along with the Neurontin. Use of both, as a 'cocktail' is usually more effective than either, alone.
I take Tramadol, and have been taking it along with the Neurontin (& now the Lyrica).
Also, the effectiveness is achieved by the timing of the doses.
I take 100mgs of Tramadol 4xday (400mgs total) at waking, 1pm, 5-6pm & bed-time.
The Lyrica is taken 200mgs 3x day (600mgs total) at waking, 5-6pm & bed-time.