I see no reason these two products cannot be used together. I would recommend, however, that you abstain from Visine use 15 minutes prior to, and 15 minutes after, using Latisse.
Latisse should not make your eyelashes shorter. Latisse works by putting more lashes in the growth phase making them longer, thicker, and darker. If you feel Latisse made your eye lashes shorter, it would be very unusual and I would report it to the company. You should stop using the product....
First of all, Latisse is very effective on African Americans- I have a number of patients who love it. Some people do get hyperpigmentation of the eyelid skin along the lash line where Latisse is applied-this does not appear to be race specific. The active ingredient in Latisse...