... countless occasions not being able to focus or get through work. I have slowly been increasing my dosage of Amitriptyline, which I now take 75mg once at night. Although I still experience migranes they are not as frequent. The other day I missed my dose at night. The next day I had a sudden case of intense dizziness and nausea. I couldn't work and had to lay down. Same thing happened the next day even though I took my scheduled dosage the night before. Woke up nauseous and it didnt go away for about 2 hours. Is this related to the medication I'm on (or missing a dose and having side effects a few days after) or could this be something else entirely??