Use of vivitonin after a stroke in an elderly dog

Our customer asked:-

My 13 year old greyhound had a mild stroke a year ago and since then has been on Vivitonin 150mg twice a day. He is happy and contented with no repeat of the stroke episode. I have seen a couple of Vets and have got differencing opinions on the dosage to be given. One suggesting that a single dose of 150mg would be sufficient to maintain his “contentedness” I just do not want to reduce and risk a stroke repeat. I have a prescription for the vivitonin but am now confused

Our reply:-

I may not help I am afraid! The merits of Vivitonin as a preventative treatment for strokes are not scientifically proven. Many expert vets working at the veterinary universities do not believe it helps at all. Many vets working in practice do use it, and most of their dogs do not have any more strokes. We cannot really tell if that would have been the same anyway, without Vivitonin. Personally I think that the Vivitonin is probably doing some good for your dog and if he seems well on it, you should continue with it. The dose is not too critical for many dogs, but ideally it should be given twice daily, not once. It is a drug which is poorly absorbed from the gut if there is a lot of food in the stomach, so you should give it with no food, or a tiny tit-bit, then give food 30 minutes later. If I were you, I might give 100mg twice daily, but it is difficult for me to comment very usefully on a dog I have not examined.