With Reglan side effects lawsuits popping up all over the place, many people are wondering how Reglan causes some of the side effects, including the lesser known side effect called blepharospasm (uncontrollable blinking).

The most popular side effect that is known to occur with prolonged use of Reglan is tardive dyskinesia, which is characterized by involuntary facial movements such as lip smacking, gum smacking, excessive blinking and involuntary movements in the appendages. While most of these conditions will discontinue after a patient stops taking Reglan, some of them are permanent. Some of the conditions caused by Reglan are untreatable, and blepharospasm is one of them.

Reglan can cause blepharospasm because it contains the gastrokinetic chemical most commonly called metoclopramide. The metoclopramide directly affects the pathways of the neurotransmitter dopamine. Information posted on http://emedicine.medscape.com says, “Dysfunction of the dopamine transporter has been hypothesized to play a role in the development of TD. However, Lafuente and colleagues did not find evidence of involvement of a polymorphism with a variable number of tandem repeats (VNTD) in the DAT gene (SLC6A3) in dyskinesias induced by antipsychotics. Thus, further research is needed to investigate the role of the dopamine transporter in the development and maintenance of TD.”

Blepharospasms are characterized by involuntary blinking (which is also a symptom of tardive dyskinesia, or TD). While most people suffering from blepharospasms do not find the condition serious in itself, it can worsen to the point where the blinking evolves into full-blown spasms that are uncomfortable and can force the eye to completely close. The eye can stay closed for hours at a time, making the patient blind until the spasm stops.

The FDA eventually issued a black box warning against Reglan for causing conditions like TD and blepharospasm among other in February 2009. The warning forced all makers of drugs containing metoclopramide to include warnings about the potential side effects. Reglan is a pill used to treat gastrointestinal disorders (acid reflux). It is not approved to be used for a period longer than 12 weeks.