Three different personal injury lawsuits were filed against Pfizer Inc. last week claiming that suicide attempts and a death stemmed from use of the drug Chantix to help alleviate symptoms of nicotine withdrawal.

The crux of each personal injury lawsuit is that staff at Pfizer did not properly inform both doctors and potential users about the potential for psychological disturbance caused by the drug, according to Reuters. All the cases were filled at the New York State Supreme Court based in Manhattan.

The suits claim the company knew that use of Chantix could possibly lead to feelings of depression and suicidal thoughts before distributing. While warnings are packaged with Chantix containers, attorneys representing those who filed against Pfizer said the warnings do not accurately describe potential side effects.

Attorney Marc Grossman wrote in one of the suits that the pharmaceutical company “intentionally, recklessly, and/or negligently concealed, suppressed, omitted, and/or misrepresented the risks, dangers, defects and disadvantages of Chantix,” Reuters reported.

Claims in two of the injury lawsuits read that two people tried to commit suicide after using the drug for help with smoking cessation. Further details about the suicide attempts were not reported.

The third suit is for wrongful death, and was filed after Indiana resident Annette Pine allegedly committed suicide after using the drug. Specific details about Pine’s case also were not reported, according to Reuters.

Pfizer spokespeople released a response after the suits were filed where they praised the drug’s effectiveness, and pointed out that it had been approved in 86 countries as an aid to quit smoking cigarettes.

“At all times, Pfizer has clearly communicated important information about the safe use of Chantix, which is available only with a prescription,” Pfizer spokesperson Sally Beatty said in the statement, also adding that Chantix has helped many smokers to quit.

“We intend to vigorously defend this medicine,” Beatty said in the statement.

All three lawsuits claim that each plaintiff used the drug as it was prescribed.

The suits also state that both the patients and their doctors were “not aware and through diligent efforts were not able to discover the risk of serious injury, and/or depressed mood and/or suicide associated with and/or caused by Chantix.”

According to Chantix.com, the drug blocks receptors in the brain that would ordinarily link with nicotine, but also causes the hormone dopamine to release. Nicotine also cause dopamine release but at a higher amount than what Chantix causes.

The site also lists that as of August 2008 over 6 million people in the United States have been prescribed Chantix for smoking cessation.

Pfizer first released the drug in 2006. Sales have since fallen while reports and concerns about side effects increased, Reuters reported.

Chantix sales fell about 15 percent in the third quarter of 2009.