As the country grapples with one of the deadliest mass shootings in modern American history, many people are asking themselves why shootings like this continue to happen in our country. Actress Kirstie Alley took to Twitter to share her theory—that psychiatric medications are to blame. 

"We have to solve the mystery of Why there were no 'shooters' or almost 0 before the 1980's," Alley tweeted. "I know one common denominator other than guns.”

She went on to blame psychiatric medications and their side effects. “One additional common denominator of 'shooters' is USA's mass usage of psychiatric drugs. A % do have side effects of VIOLENCE & SUICIDE,” she tweeted in a second post. 

Initial reports showed no evidence that Las Vegas shooter Stephen Paddock had been on psychiatric medications, according to The Washington Examiner. However, reports released on Wednesday showed that Paddock had recently been prescribed Diazepam, an anti-anxiety medication, according to the New York Daily News. 

Many people responded angrily to Alley’s comments. “Did you really just say that,” local ABC News reporter Derek Shore tweeted. “Sit down. 58 people are dead.”

Alley insisted that her comments weren’t meant to be disrespectful to the victims, but that they were opening up a necessary conversation. “UTMOST sympathy 4 the victims & their loved ones. The convo is NOT had & solutions R not found. Prayers & condolences aren't enough anymore,” she tweeted.

Alley’s comments may have been inappropriate in light of the shooting, but they could also have a real effect on people who are dealing with mental health issues. Studies, including this 2015 research from the National Institutes of Health (NIH), show that many people who take psychiatric medications feel stigmatized. 

“Medication stigma was related to internalized stigma and was common,” the study authors concluded. People are hesitant to discuss their mental health needs, especially with medications, because they are embarrassed or fear being judged. That can lead to delays in the already lengthy process of finding the most effective psychiatric medication for one's needs. 

The NIH reports that some psychiatric medications can have side effects of increased thoughts of suicide or a rise in violence. However, these side effects are rare, and most often happen when a medication is not taken the way it was prescribed, or when people suddenly stop taking a medication without the guidance of a doctor.