Can you have anal sex if hemorrhoids?

Yes and no: Hemorrhoids can be aggravated by anal intercourse, among many other problems associated to the act, including but not limitted to infections, std's, varying degrees of incontinence, bleeding and p[ain. The anus was designed as an exit, not an entrance. Use your best judgement, however i can not condone anal intercourse.

Yes: But it may make the hemorrhoids worse.

Carefully: Repeated trauma to the rectum can cause hemorrhoids or make them worse. Solution would be to use plenty of lube and dilation with fingers or similar objects. Can use hemorrhoid steroid cream on finger to apply locally internally. Use condoms to reduce risk of infections.

Sure but: Not recommended as it can be painful and cause significant bleeding and damage to the anal sphincter. The anus is generally an "exit" not an "entrance".