How do you treat bowel incontinence after prostrate seed implantation?

Well, it is rather difficult to treat, to be sure.

The problem is essentially that the rectum becomes markedly inflamed from the radiation, causing it on the one hand to tend to exude fluid into the bowel rather than absorb fluid and solidify the bowel content as is its normal function, so you tend to more liquid faeces.

On the other hand, the irritation causes it to signal the need to evacuate more than it normally would, and thus cause the urgency which results in the incontinence – the problem is not that the anus cannot close and form a seal adequately, but that the erratic urgency overrides.

Apart from the measures of which you would already be aware, of using bulking agents to firm up the faeces and avoid known aperients, there is little to suggest.

It should however settle with time.