I am on medications that make me extremely constipated. When I'm constipated, after a few weeks I suddenly get horrible horrible butt-pain. I've narrowed it down to pain in my sphincter muscle.
Going to the bathroom hurts, but it also hurts when I'm doing absolutely nothing. The pain is worse at night, and right after I eat. And it's horrible, screaming pain.
Stool softeners help a little, over time. Eating fiber helps a little--over time. Really the only thing that makes the pain go away is going off my medication--then it takes about a month.
Unfortunately the medication is Zoloft. I'm bi-polar. And trust me, we can't try something else. We've tried everything. Zoloft is the only thing that reliably works for me.
The frustrating part is no doctor that I've been to has been able to diagnose what's wrong with me. I've even had a few think that being bi-polar meant that I was making up the pain. They were bad doctors over-all, though. I've had a colonoscopy. I screamed really loudly when they were inserting the camera. But they couldn't find anything. Also, she didn't turn the camera around to look at the inside of my sphincter when she was done because even as doped up as I was, I screamed so loudly that she thought it was a waste of time.
Are microscopic fissures a possibility? Should I bring this up with my doctor?

Sorry you are in so much pain, but welcome to the forum. Sorry too that you have to be here, but you could not have landed in a better spot!
Fissures can be very small and often difficult to see, just like a paper cut. You mention 'your doctor'. If the doc is not a Colon and Rectal Surgeon (don't have to be operated on just because the doc is a surgeon), but a GP, they are not all that good at recognising fissures, nearly always diagnosing hemmies and often prescribing the wrong thing. I had to get the surgeon to look for the fissure (not fun, screaming etc.), as my GP was useless.
Basically, if you are having trouble with your medication, the 'secret' is to make sure that you are not constipated. People on here talk about toothpaste consistency, and that is what you want to aim for. Miralax is a wonderful laxative that draws water into the colon, hence softening the stool. So is Milk of Magnesia. Most swear by Miralax, but the secret is getting what is good for your system. Water and fiber are also important, but you probably know that.
Just in case you don't know, we have two sphincters. The external one that we can control, and the internal one which is the bug bear, which we cannot control and which goes into spasm on us if a fissure forms, and for all variety of other reasons. Here is a link to information about ANAL FISSURES on the forum with a bit more info - http://anal-fissure.org/t4541-anal-fissure-as-at-jan-2012
Hope this is a help to you. Come back and ask any more questions you might have!
All the best,
Sav
All the

Bless you!
I've seen about ten doctors. Many of them try to blame it on my Bi-polar. I always hate it when that happens because I have to find a new doctor. If a doctor won't trust me to report my own symptoms when I'm on medication and the medication is working then I refuse to even try to work with them. Hallucinations are not a symptom of Bi-polar. I even had my psychiatrist write me a note.
Mostly I've seen Gynecologists, endocrinologists, and one GI specialist. You're saying I need a colon and rectal surgeon specifically? I'll see if I can track one down. I have a gyno appt tomorrow and I'll ask her to refer me. I suspect that when I get them, they are on the inside sphincter. And it hurts like a mother.
I have blood in my stool a lot. It's been tested but the most I get is "Yeah. We don't know what's causing it. You bleed. Deal with it." I almost always have mucus.

Hiya,
Sorry to hear of your plight and all the pain.
It really irritates me that GP's will use other issues at times to blame when often there's something else underlying. Savaici is spot on in saying you need a Colorectal specialist opinion on this. Please shout at your GP to get you referred!! Pain inevitably indicates an issue and I am 100% certain it''s NOT in your head! Bi-polar or not. It's ludicrous and insulting to even suggest that and I'd be fuming!!
My fissure was not externally visibly and needed an examination under anaesthetic to be detected as with a lot of others. So, this could well be the case for you...I'm not bi-polar but have to take Sertraline (Zoloft) also as I have depression and OCD issues, which are helped hugely by taking this. It doesn't seem to have had a major impact on my bottom issues as with yourself but I do drink an awful lot of water, try to eat as well as possible (fibre!) and use Lactulose as a stool softener & Olive oil....
Good luck with it all and get that referral to someone who will actually understand how you're feeling and be able to take the steps to get you sorted :)

DieFree, another link for you about fissures, which I think is quite good for explaining where they are in language for laymen (us :D ). This is:
http://www.medicinenet.com/anal_fissure/article.htm
If your doctors are making unprofessional deductions at what is wrong with you, always get your medical records, and report them if necessary. Why do some of them think that their education entitles them to deride people in pain. I am a great believer in being an advocate for my own health and won't take any BS from any of the docs, or their office staff...but I am very polite about it.
When you find a gem of a doctor, however, hang on for dear life! And they are out there.
Ever the Optimist has given you some good ideas too. I also take olive oil.