A California woman is suing Pfizer Inc., claiming the drug maker misled physicians and patients about the safety, effectiveness and side effects of the anti-depressant drug Zoloft.

The 19-page complaint, filed Friday in Los Angeles Superior Court, contends that Pfizer buried evidence showing the drug was no more effective than a placebo and its users tended to develop an array of side effects, including withdrawal symptoms, dependency, convulsions and psychosis.

The lawsuit also accused the New York-based drug maker of suppressing data indicating the drug increased the risk of suicidal and violent impulses in users.

"Pfizer has engaged in repeated and persistent false and misleading conduct by misrepresenting, concealing and otherwise failing to disclose to physicians and other prescribing health care providers information in its possession ... concerning the safety and effectiveness of Zoloft," the lawsuit claims.

The woman, Roberta Madison, was identified as a nurse and doctor of Public Health who lives in Los Angeles.

Madison's claim does not stem from personal injury, the suit states. Instead she decided to sue on behalf of all Californians who "have been misled about Zoloft," the law firm representing her said in a statement.

The suit asked the court to order Pfizer to pay an undetermined amount of money in restitution, including proceeds from Zoloft sales, to users of the drug in California. It also seeks a court order forcing Pfizer to give access to Zoloft research studies.

The lawsuit asserts that while Pfizer has been known to publicize positive information about Zoloft, the company has "intentionally withheld and concealed" negative information on the drug, ultimately hampering physicians' ability to determine whether to prescribe the drug.

The suit also claims early Pfizer studies of the drug's effectiveness were negative, failed or were neutral, and the majority of the studies showed there were no clinically or statistically significant differences between the drug and placebo, but the drug maker concealed the results.

"Many Pfizer studies not only failed to demonstrate that Zoloft is efficacious, they clearly demonstrated that Zoloft is associated with serious, severe and sometimes fatal side effects," the suit claimed.

A message left after hours with a Pfizer spokesman was not immediately returned Friday.