I'd like some recommendations on supplements for immune system health for an 8 year old female cat

Hey everyone. I am looking for some recommendations on supplements for immune system health for an 8 year old female Domestic Short Hair cat. And yes, I am speaking about Precious. I am wanting to start her on a daily supplement, possibly a general vitamin/mineral supplement because she is prone to colds due to chronic ear allergies. I would prefer something that can be given as a treat if possible.

I would supplement with Lysine since your kitty is prone to colds.  Give 500mg per day.  You can find it in treats and/or use it in powder for.  I use it in powder form and mix a little with canned food for my crew.

Yes I would also make the suggestion to consider giving Precious L-Lysine which is a supplement that specifically works to boost and support the immune system. I am currently giving this to Max (avatar pic) to help prevent the rodent ulcers he gets occasionally. For more information and other opinions on this, there is an older thread on this supplement with many replies, further down the list in this Cat Health forum. Worth checking out.

Thank you everyone for your advice. I will discuss the possibility of giving L-Lysine to Precious at her next veterinary visit in the next couple of weeks.

There is also a product called Transfer Factor.  I've never used it, but some of our member have, and have had nothing but good to say about it (as far as I recall)