A. The medication you're thinking of is called Slentrol ®. It's the first ever prescription weight loss pill for dogs and was approved by the FDA back in February. It is often considered to be similar to Orlistat, which is marketed for human weight loss as Xenical and Alli. However it is somewhat different. Slentrol is a type of drug known as a MTP inhibitor. It works by decreasing fat absorption and promoting satiety (the feeling of being full). The human drug Orlistat is a lipase inhibitor and mainly works by blocking fat absorption. Hence the nasty side effects (increased stool, oily stool, frequent defecation) seen with Orlistat should not happen. However, vomiting and diarrhea are possible side effects.
The manufacturer of Slentrol, Pfizer, claims it is very effective, with one study demonstrating 20 percent weight loss after six months in overweight Labrador retrievers. It does not appear to have any long term side effects, but as with any new drug, only time will tell for sure. I am aware of several veterinarians who have recommended using the drug for dangerously obese dogs. Your dog might be a good candidate, since he may need to have his weight loss "jump started" so he can start exercising. Stopping the drug will cause a return of appetite and weight gain unless food intake is controlled. It is usually taken for several months and is not prohibitively expensive.
And to answer your next question, no, Slentrol cannot be used in humans or cats, because of possible effects on the liver.
--Dr. Heidi Strand is a veterinarian for the East Bay SPCA in Dublin. She has lived in the Tri-Valley for 10 years with her family and an assortment of four-legged friends. Questions can be mailed to 315 Diablo Road, Suite 100, Danville 94526; or e-mailed to firstname.lastname@example.org. Her column runs every other week.