In both cases, cloth undergarments would be next to your skin, except for seals at the neck, face, wrists, and possibly ankles. If you have an allergy to both latex and neoprene, you may still have some problems as these are the two materials used for seals in dry suits. For many people, though, dry suits are not a practical solution. Either the waters they dive in are too warm for a dry suit, or the suit is too expensive, especially if they dive infrequently. For those reasons, we will examine the possibility of wet suits and determining the cause of the allergy.
Some divers exhibit an allergy to wetsuits, or the materials used in their construction.
Their skin may become red, inflamed, and itch. Wearing a Lycra skin underneath does not eliminate the irritation for some of these divers, while others claim it is reduced. Perhaps a Polartec skin might offer more protection due to its greater thickness, though it can be counterproductive thermal wise in a well fitting suit. It breaks the seal at entry points and allows more water in. Some have benefited from having the inside seams covered with heat-sealed tape, and have found that it prevents a reaction.