Promethazine HCl Tablets 50 mg by Amneal is a prescription medication used to treat a variety of conditions including allergies, motion sickness, and insomnia. It contains the active ingredient promethazine hydrochloride, a sedating antihistamine that works by blocking the effects of histamine in the body. It is available in tablet form and is manufactured by Amneal Pharmaceuticals.

Promethazine HCl tablets 50 mg contain the active ingredient promethazine, which belongs to a class of medications called phenothiazines. It works by blocking the action of histamine, which is a chemical released by the body during an allergic reaction. Histamine is responsible for causing symptoms such as itching, sneezing, and runny nose. By blocking histamine, promethazine helps to relieve symptoms such as itching, sneezing, and watery eyes.

Promethazine also has sedating effects, which can make it useful for treating nausea and vomiting. It works by blocking a certain chemical in the brain (dopamine) that triggers nausea and vomiting. This sedating effect may also make it useful for treating other conditions such as motion sickness and allergies.

Additionally, promethazine has anticholinergic effects, meaning it blocks the action of another chemical in the body called acetylcholine. This can help to reduce symptoms such as sweating, nausea, and vomiting.

Overall, promethazine HCl tablets 50 mg work by blocking the action of histamine, dopamine, and acetylcholine, providing relief for various symptoms such as itching, sneezing, nausea, and vomiting.