Before we get into the different types of Drain Cleaning products, it's important to point out that they can prove hazardous and harmful to YOU and your pipes. Caustic and acidic drain cleaners should never be used in combination. They neutralize each other and may generate large quantities of heat and gas. This may cause a potentially harmful, violent eruption from the drain. The combination can also cause severe injury to eyes and other tissues and may damage tubs and toilets. Unmitigated chemicals can cause holes in pipes and damage significant plumbing fixtures that could cost thousands of dollars to replace, so it's probably not the Drain Cleaning solution you're looking for.