Eli Lilly & Co., the producer of the popular antidepressant Cymbalta , is facing a spate of litigation over injuries associated with the drug. Plaintiffs allege that Cymbalta can cause severe withdrawal symptoms, including dizziness, nausea, headache, fatigue, paresthesia, vomiting, irritability, nightmares, insomnia, diarrhea, anxiety, hyperhidrosis, and vertigo within 12 hours of missing a single dose.