There are a few options, Julie, though I can't say they're the same or equivalent - just simulations
First, tight undies and tucking can do some of these effects. Turns off the testicles' primary function, making sperm. Also affects LH, FSH, and T, and DHT. I don't know any numbers, though.
Second, add EXTRA HOT showers or baths, and allow the testicles to stay toasty for a long time. Amplifies the effect above, and was explored as a means of male birth control. The scientist who did the study (n=1, himself) was looking into population growth issues in India, and wanted a cheap and reversible male birth control. He tested it for a week or two, and found he stlll produced enough testosterone to make things interesting, but no sperm. After a short period, he tried to reverse the process, and things went back to normal. Long term effects remain unknown.)
You can also use chasteberry to make your desire go WAY down. It stops DHT, and will therefore reduce the drive. After a period, it will also make the party of little interest, too. I'd guess it approximates a woman's sex drive more, since there's little interest in orgasm, though things are still pleasurable. Just hard to cum, makes it more work than it's worth, and makes the head desensitized. I know that from personal experience.
Progesterone cream on the head will also kill desire overnight (no pleasure from penetration or masturbation).
Put it all together, especially with tucking or metal chastity (heat around the balls again), you'll make things calm WAY down. Also, with a chastity, you'll have little space for contact shifting sexuality to other outlets. Whether that means breasts or other play depends on your individual wiring.
Also, if you're on SPirotone, it's already acting on some of this. Thyroid medications could be repurposed, they'll interfere with LH and FSH, though I don't know many details - YMMV, do lots of research, and then think twice again - messing with thyroid can be BAD. As in fatal.
I'd also go review Lotus's masterposts on herbs, as any testosterone agonist should have some effects, too, and estrogens will wipe the desire out quickly...
Most of these are semi-permanent, though. If you're not at he point of having children, it might be worth it just to do it, and then if you want him active again, use testosterone....
But it seems very cross-purposes to being HERE, in some ways. ;-)
-Dianna