Thank you for the additional information.
There are several issues to discuss in this situation.
From the perspective of the migraine headaches, there are two general approaches to treatment.First is treatment that is done to stop the migraine headaches when they happen, also called abortive treatment. Second is the use of medicines to prevent the migraine headaches, also called prophylactic treatment.
You do not mention that you have been tried on a triptan. The triptans are frequently used to help abort a migraine headache and have the greatest success rate of medicines that are used for abortive treatment. Phenergan and chlorpromazine are also used, but have lower overall effectiveness. One of the limiting factors in the use of oral medicines for abortive treatment are side effects of the medicines or difficulty in tolerating oral medicines because of nausea and vomiting that frequently occur with migraine headaches. In people that have difficulty with pills for abortive treatment, there also is a newer technology available, called transcranial magnetic stimulation, which can be considered.
There are a number of different treatments that can be used for prophylactic treatment, including the Topamax and Botox recommended by your Neurologist. There are actually many other options, including beta-blockers, calcium antagonists, and certain antidepressants.
As for the risk for TIAs. It is true that migraine headaches, and particularly migraine with aura, increase the risk for stroke. However, identifying TIAs can be difficulty. Migraines can cause a variety of transient neurologic symptoms. It is also possible to have migraine-induced neurolpogic deficits without an actual migraine. If all of your episodes of confusion or difficulty speaking were associated with a migraine, that would be less worrisome. But if there are episodes of neurologic symptoms that are not associated with a migraine, that can be more difficult. If neurologic deficits occur both with and without a migraine, and the symptoms are similar, it is more likely that all of the neurologic symptoms are due to migraines rather than TIAs. But if there are neurologic symptoms that occur without migraine, that would be more worrisome, although it still could be due to migraines. In this situation, performing an evaluation for possible TIAs would be appropriate, such as a carotid ultrasound.
If I can provide any additional information, please let me know.