The privately-held company in February said it stopped promoting opioids to physicians after widespread criticism of the ways drugmakers market highly addictive painkillers.
In Texas, Attorney General Ken Paxton also alleged the company misrepresented that there is no "ceiling dose" of their opioid drugs, and that doctors and patients could increase dosages indefinitely without risk. "It represents a callous disregard for human life that Texans simply can not and will not tolerate".
In 2016, 1,375 Texans died of opioid-related deaths.
More than a year ago, Stenehjem's office, together with a coalition of other states, launched an investigation that obtained hundreds of thousands of documents from the manufacturers and distributors of various opioid prescription medications.
Slatery filed his suit in Knox County Circuit Court.
These sources appeared to be neutral advocates for the use of opioids to treat chronic pain but were actually paid mouthpieces of the manufacturers, according to a statement from Attorney General Pam Bondi.
According to the lawsuit, Purdue "realized over $35 billion in sales from OxyContin since it began marketing the drug in 1996".
"We are preparing a lawsuit against Purdue Pharma for its alleged deception and reckless disregard for the health and wellbeing of New Yorkers, Underwood said in a statement".
Paxton says that amount will be determined once his office finishes looking over evidence.
"The prescription and illicit opioid abuse crisis is a multifaceted public health challenge", the message states, "and as a manufacturer of prescription opioids, we have a responsibility to join the fight".
Anesthesiologist Dr. Carlos "Nick" Lee explained to legislators how more doctors are trying to strike a balance when managing a patient's pain, but it's often hard.
"Even though we have separate lawsuits we can work together for the same goal of trying to hold the folks that helped create this problem accountable", he said.
Lee said doctors are looking for other treatment options as well.
"Today, I filed a lawsuit against Purdue Pharma".
Joseph has felt that pain first hand and, since he's started working at Recovery Unplugged, he sees clients struggling with opioid addiction on a daily basis.
Lawsuits filed against Oxycontin maker Purdue Pharma and other drugmakers by Tennessee and Florida cast more doubt about the viability of settlement talks aimed at addressing the US opioid epidemic.
In its own statement, Purdue said the company "vigorously" denies the allegations and looks "forward to the opportunity to present our defense".