Para-Aminobenzoic Acid is a chemical that is found in the folic acid vitamin. This is needed to treat infertility in women. Also, it is needed for the treatment of rheumatic fever, constipation, arthritis, headaches and systemic lupus. This is also used to make supplements that darken the gray hair, makes the skin look younger, and prevents sunburn. Para-Aminobenzoic Acid is included with a crystalline substance. This is a vitamin B complex and works as an essential nutrient.