In addition to the active ingredient sennosides, Ex-Lax contains acacia, alginic acid, carnauba wax, colloidal silicon dioxide, dibasic calcium phosphate, FD&C blue no.1 aluminum lake, magnesium stearate, microcrystalline cellulose, povidone, sodium benzoate, sodium lauryl sulfate, starch, stearic acid, sucrose, talc and titanium dioxide. Sennosides are a stimulant laxative.
Sennosides work by retaining water in the intestines, causing the intestines to engage in peristaltic action, a smooth muscle reflex that is necessary in order to have a bowel movement. It takes from six to 12 hours for the ingredient to work in most people. The recommended dosage depends on a person's age.
Sennosides sometimes cause side effects, including abdominal cramping or discomfort, diarrhea and nausea. Those who overuse Ex-Lax and other laxatives containing sennosides risk becoming dependent on them to have a bowel movement, as well as possible damage to their intestines. Ex-Lax is available in several strength levels, each of which contains varying amounts of sennosides.
Acacia, one of the inactive ingredients in Ex-Lax, is a dietary fiber soluble in water. It is used in many medications to reduce throat and stomach inflammation as well. Carnauba wax, derived from trees in Brazil, is used to make the coating on Ex-Lax tablets.