You can use a skin barrier product. Moisture barriers, sometimes called skin protectants, are creams or ointments that shield the skin from exposure to irritants or moisture. You would apply this product on the shaft of the penis (skin) before you put on the condom catheter. Another thing you could use is a stoma adhesive product. This can also be applied over the penis but is more often used to help the product stick to the skin. If the problem is skin irritation and breakdown I would use the barrier product. You should be able to find these at a medical supply store. Do not buy any skin product it has to be a moisture barrier product.