Question: what is the fastest acting over the counter laxative?
Answer: Stimulant laxatives are the fastest-acting, such as include aloe, cascara (Nature's Remedy), senna compounds (Ex-Lax, Senokot), bisacodyl (Dulcolax, Correctol), and castor oil. Saline laxatives or enemas such as Fleet Phospho-Soda, milk of magnesia, and magnesium citrate.