Report: Junior Seau battled insomnia

Friends of Junior Seau said the former NFL linebacker suffered from insomnia, and at least four of those friends said Seau regularly took the prescription drug Ambien, according to a USA Today report.

Nancy Emsley, who frequented the same gym as Seau, told USA Today that she repeatedly stressed to Seau the importance of getting eight hours of sleep after taking an Ambien pill.

"He told me he usually woke up around 1 or 2 (a.m.) and couldn't go back to sleep," Emsley told USA Today.

The 43-year-old Seau was found shot to death at his home on May 2. His death has been ruled a suicide.

Ambien is the most recognized brand name for zolpidem, a drug usually prescribed for sleep disorders. Ambien's FDA-approved prescribing information includes warnings that suicidal thoughts or actions have been reported by depressed patients using that class of drugs.

Instructions are also included that tell users not to take Ambien if they consume alcohol -- which friends said Seau did -- or if they are unable to get a full eight hours of sleep.

Mark Walczak, Seau's former teammate with the San Diego Chargers, told USA Today he witnessed Seau taking a prescription sleeping pill in 2005, when Seau played for the Miami Dolphins.

"I know he's had a very difficult time sleeping over the years," Walczak told USA Today. "I think it's gotten worse and worse. Lack of sleep creates huge anxiety."