Abbott Laboratories is currently the target of a product liability lawsuit, which was filed in May by Jamie Bixby in the U.S. District Court for the Northern District of Illinois. In the suit, Bixby alleges that her use of Abbott’s blockbuster drug, Humira, caused her to develop optic nerve damage and permanent vision problems.

Humira is a “biologic” drug which is part of a class of medications known as TNF blockers. Launched by Abbott in 2003, Humira has become one of the company’s top-selling products and is also one of the world’s most lucrative drugs. In fact, in 2010, Humira reported worldwide sales of $6.5 billion. The drug was originally approved for use in the treatment of arthritis, but was subsequently approved as a treatment to reduce the signs and symptoms associated with moderate to severe Crohn’s disease, a condition in which the body attacks the lining of the digestive tract.

Bixby began using Humira in April of 2008, as a means to treat Crohn’s Disease. By May of 2008, Bixby indicated that she began experiencing severe headaches and pain in her left eye, which quickly gave way to extreme blurred vision with blacked out areas. Bixby was ultimately diagnosed with optic neuritis from Humira in both eyes. In the complaint, Bixby specifically claims that if Abbott had warned her or her gastroenterologist “that Humira could be the source of her eye pain, she would have immediately discontinued taking the drug and would have immediately obtained proper emergency medical treatment.” Bixby further alleges that Abbott downplayed the risk of Humira side effects, including the risk of Central Nervous System demyelination.