How effective are steroid creams at treating phimosis?

Depends: It really depends on the cause of the phimosis. If the cause is balanitis xerotica obliterans then steroid creams are 0%. Effective. If bxo is not the cause then one study suggests that a 3 month course of treatment is 50% effective.

Children do better: Than adults. 70 -80% respond to steroid creams, if applied correctly. This means pulling back on the foreskin and appling cream to all the skin preventing retraction, or are of narrowing causing a "waist" if the tight foreskin can be pulled over the glans. Apply twice daily for 3 months.Remember always to pull tight foreskin back over glans to avoid paraphimosis. Unfortunately 50% re-phimose.

80%: But they have to be prescription strength and applied twice daily for 2 months. They are very safe and effective.