Appropriate substitutes for Calan and Aldoril are available. Ulcers are sores. They appear when the covering of a tissue is abraded, irritated, infected or deprived of oxygen. For example, a decubitus ulcer is a skin sore that forms on debilitated patients who are bedridden. Peptic ulcer is a sore in the lining of the small intestine, often the result of a bacterial infection with a microorganism called H. pylori.
Various cancers can ulcerate when they outgrow their blood supply.
Even shins can ulcerate in the presence of varicose veins. I do not know the cause of your bladder ulcers. Since the bladder is lined by skin-cells, irritation or infection of one kind or another could produce areas that become denuded and ulcerated. Treatment would have to be directed toward the cause, rather than to the ulcers themselves. A urologist should be able to answer your questions, after appropriately testing you.