As is the case with many prescription medications, the interaction of Neurontin with alcohol, other prescription drugs, painkillers, and sleep medications can cause potentially serious side effects. In particular, these interactions can enhance the concentration of Neurontin in a patient's body. Elevated levels of Neurontin also appear to adversely affect children under the age of 12, and older patients as well. The most serious side effect with which Neurontin's manufacturer is charged with failing to adequately disclose and/or warn is the increased risks of suicidal behavior in patients prescribed Neurontin. By 2006, more than 300 lawsuits had been filed asserting that consumers had been injured by taking Neurontin, due to Pfizer's failure to warn of the potential side effect of suicide and suicidal actions, and for illegally marketing the drug to treat medical conditions not approved by the U.S. Food and Drug Administration ("FDA"). Studies show that patients taking Neurontin had approximately twice the risk of suicidality as pateients not taking Neurontin.