It is a good questions. Some people tend to respond to certain probiotics while others do not. The only lactobacillus / bifidobacteria based probiotic that has helped me is VSL#3. I hate to recommend it because it is so awful expensive and most insurance companies do not cover it yet.
$30 is probably typical for most brands. However, you can usually find a better deal online.
6MP, Asacol, Rowasa
VSL#3, Florastor (Saccharomyces boulardii), Mutaflor(E. Coli Nissle 1917)
TSO (helminthic worm therapy)
Psyllium Seed Powder, Turmeric Extract, Fish Oil, SeaCure
Multivitamin, Folic Acid, Vitamin C, Alpha Lipoic Acid, L-Carnitine, L-Taurine
Ulcerin I and Ulcerin II (ayurveda herbal medication for UC)
Low Dose Naltrexone 4mg