Can a sexually active male use gardasil 9 if they are over 45? i'm 53. i use a condom but am worried about oral transmission of genital warts?

The vaccine is harmless regardless of age. However, at age 53 there probably is little value in vaccination: assuming an average sex life, you likely have been infected with most HPV types covered by the vaccine, including HPV 16, the only type that causes throat cancer due to HPV; vaccine will not protect you further. And probably not covered by insurance at your age, costing up to $1,000.

The recommended age is 45yrs. if you have not had them by now then chances are very low in your scenario. Most sexually active men can have the virus and not develop the disease. But you can try your doc to see if he will give the shot