The Food and Drug Administration has approved a drug made by Pfizer to aid the weight management of obese dogs.

Pfizer will release the liquid formula Slentrol for around 5 percent of U.S. dogs that are 20 percent beyond the ideal weight.

FDA says the drug's "mechanism for producing weight loss is not completely understood," although it leads to less fat absorption.

Pets who are overweight risk heart disease, diabetes and joint problems, according to the government agency.

Slentrol instructs that a veterinarian must manage the monthly weight change of a dog on the drug and adjust the dosage accordingly.