Using cocaine and alcohol together at the same time can lead to an increased risk of committing a suicide, warns a study.
According to researchers, specifically those using both, the chance of attempting suicide again were 2.4 times greater than among people in the study who were not.
"However, reporting both alcohol misuse and cocaine use was significantly associated with a future suicide attempt," said lead study author Sarah Arias from Alpert Medical School of Brown University in the US.
"Patients who have potentially co-morbid alcohol and cocaine use may be at a higher risk. Findings like these can be useful for informing suicide risk assessment," Arias added in a paper published in the journal Crisis.
The team examined 874 of suicidal emergency department (ED) patients who presented at one of eight emergency departments around the country between 2010 and 2012.
Individuals included in the analysis received standard care and either reported a recent suicide attempt or actively engaged in suicidal thoughts at the time of the initial ED visit.
Of the entire study population, 298 misused alcohol, 72 were using cocaine and 41 were using both.
The researchers found was that although people in the study reported misusing many different substances, including marijuana, prescription painkillers, tranquilizers and stimulants, but only cocaine and alcohol appeared to have a significant association with suicide risk.
"One unexpected finding was that, when examined independently, alcohol use had no significant association and cocaine use had a borderline significant association," researchers stated.
Older people, meanwhile, were more likely to have an association between substance misuse and suicide.
"These disparate findings emphasise the complex interaction of sex, substance use and suicide attempts," the authors added.