Due to a recent bladder infection I have had to look into this matter.

Male pads seem to come in three basic types, with increasing levels of absorbancy.
A small cup shaped pad which fits into the front of the pants.
A thicker nappy (diaper) quality pad for the front of the pants only.
Full incontinence pants (no personal experience with these).

The first two are quite discrete, at worst you will get a little enhancement to your "natural assets".
The pants are quite high cut and can show above trousers if you are not careful.

In the UK the only brands readily available seem to be Tena and Boots. Both are effective.