Casodex (bicalutamide) works as an anti androgen as a selective antagonist of the androgen receptor site. It does not reduce Testosterone levels. It just makes no room for Testosterone at the place where T works it's magic, therefore T and DHT are rendered ineffective. Because of the complex nature of our bodies hormone regulating system, some men even find an increase in their T blood levels. This increase in T has no effect.
The main side effects are breast enlargement and tenderness, muscle weakness, decrease in libido and erectile function and a decrease in liver function. Most of these side effects are to be expected and welcomed if that is part of your overall goal. The decrease in liver function only effects 3.5% of users as compared to about 2% for placebo.
There are other side effects, but they are all listed at less then 1% of users experiencing these side effects. Anything less than 1% is considered a possible but not likely side effect.
If anyone is going to take bicalutamide, they need to have their liver functions tested regularly and stop the bicalutamide at the first sign of liver damage. Bicalutamide is not a miracle drug. It has risks and benefits. For many of us with MTF dysphoria, the benefits far outweigh the risks, but this drug needs to be carefully monitored by your doctor.
As a final comment, once the major source of Testosterone is removed, there is no need to continue bicalutamide. The same can be said once you are on Estradiol for about a year or so when your T levels naturally drop.