Dear Dr Salkin,
Thank you for your answer. It is much appreciated.
At the time of diagnosis, our vet said he did not think AZT would contribute much to the cat's well-being, apparently, since it is not as effective in cats as in humans, and cats can live a fairly normal life with FIV, as has been our experience so far.
Now that his symptoms have worsened,as it were ,I'll take the cat to see our vet but, considering his age, I do not wish to cause him too much unnecessary distress. Visits to the vet cause him to panic, with the result that he disappears afterwards, making it difficult to ensure that he receives his medication. I agree with you that a more potent anti-convulsive drug may be needed, but I'll have to have it prescribed. I shall also discuss further diagnostic tests re a brain tumour with our vet, but he will probably be of your opinion.
I looked meningioma up. Since it seems to grow slowly, the cat's age is certainly a basic consideration.
Thank you again for your very valuable advice.