Echothiophate

Echothiophate is a parasympathomimetic and organophosphate which binds irreversibly to cholinesterase. Because of the very slow rate at which echothiophate is hydrolyzed by cholinesterase, its effects can last a week or more.

Clinical uses
Echothiophate is used as ocular drops in the treatment of chronic glaucoma and in some cases, accommodative esotropia. It is available under several trade names such as Phospholine Iodide (Wyeth-Ayerst).

Shortage
Wyeth Pharmaceuticals stopped manufacturing echothiophate iodide (phospholine iodide) in the US in 2003. After contacting the American Academy of Ophthalmology (AAO), Wyeth rescinded their decision and, according to AAO public relations representative Michelle Stephens, the AAO and Wyeth were in talks for about a year about manufacturing it.

In the meantime, a worldwide shortage of the drug has occurred.