Of all the various rules, regulations and warnings issued by the U.S. Food and Drug Administration (FDA), the most serious is a black box warning. The name refers to text that must appear in a black box on the drug package insert, warning users of very serious side effects.
In February 2009 the FDA released a black box warning for metoclopramide, better known in the U.S. by its trade name of Reglan. Prolonged use of Reglan has been associated with tardive dyskinesia, a muscular disorder in which the patient has frequent uncontrollable movements of the face and mouth, such as eye rolling, rapid blinking, grimacing, chewing motions, lip smacking, pursing and puckering of the lips, and tongue motions. In some cases other extremities are affected like fingers or legs.
Although a study linking Reglan with tardive dyskinesia was published in 2004, and the FDA's warning has been in place since early 2009, many people are still unaware of the dangers of prolonged use of the drug. Metoclopramide has been in use since the 1960s to treat nausea and vomiting, heartburn, slow emptying of stomach (often following surgery), and to speed healing of ulcers and sores in the esophagus in people with acid reflux. It even has been used to treat migraine headaches. Its primary function is to speed the movement of food through the digestive tract.
Scientists believe that metoclopramide (and similar medications, called neuroleptic or antipsychotic drugs) works by blocking the signals that regulate the functions of the body's organs and other systems. These experts theorize that when used over a prolonged period of time, such drugs cause the body to lose the ability to regulate certain bodily movements.
Just how much exposure to Reglan is acceptable is not known. The FDA's warning states that the majority of tardive-dyskinesia patients who used metoclopramide had been taking it for more than three months. The FDA warns users to avoid prolonged treatment with the drug, and says that the elderly (especially older women) are at greater risk.
Anyone taking Reglan for any length of time should be aware of its risk, and discuss with his or her doctor the relative benefits of continued use. Anyone experiencing tardive-dyskinesia symptoms that may be associated with Reglan or a similar medication should talk with an attorney who is experienced in medical malpractice cases.