I know you guys are not doctors, but do you know someone or yourself that this has happened too?

My dad has never had a seizure before. He is a diabetic. Chronic knee pain, hip is dislocated because they think he has deterioration in his disc. So he's in a lot of pain and under a lot of stress. They recently upgraded his dose of gabapentin from 300 to 600 mg. So that's some back ground info. Anyway, we were unusually active that day, went to the fireworks. Four hours after the fireworks, his whole body was shaking uncontrollably. His blood sugar was fine and he was coherent, he was answering questions and everything. They did several tests over a 4 day span, an mri, ekg, eeg, 6 blood tests, urine and a cat scan. They all came back normal. He was having multiple seizures in the hospital lasting between 6 mins to 20 seconds. Anyone have an idea what is going on?
I know you guys are not doctors, but do you know someone or yourself that this has happened too?
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