My husband has issues with stamina during sex. what can be done to increase to more than a minute?

Depends: Stamina implies physical ability to keep up with it. If he gets tired so quickly, needs to see a doctor. If you are talking about pre-mature ejaculation, the simplest solution is de-sensitizing spray or lotion that is sold in pharmacy next to condoms, or in 'novelty' shops. There are medications, ssri, like zoloft (sertraline) and prozac, but there are other side effects you should discuss with doctor.

Erectile dysfunction: Premature ejactulatiom is a frequent cause of male erectile dysfunction. It occurs due to hyperstimulation of the parasympathetic nervous system. Topical numbing agents like oragel may work for mild cases. For severe cases several prescription medications may be helpful. Also try to reduce stress.