So basically Hyoscyamine is what you are taking right now.. as well an an occasional anti-anxiety med(emergency pill from your mom).
What over the counter products have you tried?
Have you tried calcium? Calcium is actually a wonderful product at treating diarrhea. It has to be Calcium CARBONATE, and not citrate... Caltrate Colon Health is a popular choice. The way it works is by not working actually. Calcium carbonate doesn't get absorbed into the body/bones as well as citrate and the remaining unabsorbed calcium makes its way to the intestines soaking up water along the way. Taken once with each meal, you may find some relief from loose stools and urgency.
Have you worked fiber into your diet at all? Fiber works for both diarrhea/constipation, and you need at least 25-35 grams of fiber a day for your intestines to function the way they should. A good fiber supplement is something like Metamucil. You want to make sure its soluble fiber, and not insoluble fiber. Start SMALL, and work your way up. Your body needs to adjust. Truthfully, you may have tried this before, but it can take some time for your body to adjust, so I would try one more time with the calcium.
As far as medicine goes.... Have you ever taken an anti-depressant? Anti-depressants like tri-cyclics (Tofranil, Elavil) can cause constipation, so they are very useful in treating IBS-D.
If you've tried one before, and found it didn't help you, you may want to think about trying another one. It took me 4 tries to find one that worked best for me. Tofranil worked wonders for me for a year.
Another one to look into is Remeron. Remeron works on the same receptor in the intestines as Lotronex, helping to slow transit time down in the intestines, therefore relieving diarrhea.
Lotronex has been a miracle drug for some. You might research it a little further to see if it would be a medicine for you, as it is only prescribed for people with severe diarrhea predominant irritable bowel syndrome. My gastro doctor says this medicine is very safe if taken as prescribed, despite its warnings. The majority of the people that had problem with this medicine were elderly. You might want to discuss this medicine with your doctor, as it has given many people their lives back.
Neurontin is another medicine that is being prescribed more frequently to treat the pain associated with irritable bowel syndrome. It has an on-label use of treating post-shingles pain, but many medicines are used for different things. My gastro just mentioned this to me at my last visit, and I will probably end up trying it in about 8 weeks.
It really is a trial and error with medicine. You often times will need to try several different medicines before you find one that really works for you.
I also might add that some people have found relief with taking Buspar(an anti-anxiety medication) and Nulev(an anti-spasmodic like Hyosycamine) together.
This is a start, reply back if you would like to discuss further