numb in the head please help!!

Hi I'm new here too,
My husband was diagnosed with Trigeminal Neuralgia a couple of months ago after a few weeks of being in horrendous pain and giving into seeing a private Neurologist and having an MRI scan.
He is on a relatively low dose of Tregetol (spell) which stops the pain, but if he rests his head on the back of the sofa for any longer than 5 minutes he says he has a numb feeling starting at the back of his head moving round to his ear and face and his teeth start to throb (he has the same feeling at night and when he wakes up in the morning).
He has started to doubt the TN diagnosis as the pain he felt during the attacks wasn't 'lightning strikes', it was almost like cramp without the stiffening of the muscles and it crept around his face as opposed to stabbing. He could feel it coming on in his gums/teeth, then it went to his ear, then all over the left side of his face upto the top of his head.

Does anyone have any thoughts/suggestions?

Thanks
J