Yes. If it has a Model Number marked in the yoke and it is a steel frame, you can use +P.

+P is not like a bomb going off, and to be honest, it is not as hot as the old 38/44 round, which S&W at one time certified for use in K frame M&Ps in order to compete with Colt's Police Positive and Official Police models, which were certified for the 38/44.

Use +P to your heart's content. Your wallet will wear out long before your gun.