Study warns over intentional medication overdose
Clinicians should consider the risk posed by certain medication when determining treatment for patients at risk of self-harming or who have a record of doing so, according to a new study.
The research investigated non-fatal and fatal intentional drug overdose (IDO) and found that particular classes of antidepressants and some common painkiller drugs were associated with a “significantly increased risk of death following intentional overdose”.
The research, which was carried out by a group led by Caroline Daly of the National Suicide Research Foundation, is entitled ‘A national case fatality study of drugs taken in intentional overdose’.
It was published in the International Journal of Drug Policy.
It used data from the National Self-Harm Registry and National Drug-Related Deaths Index 2007-2014, with 63,831 non-fatal and 364 fatal IDOs examined for the study.
“Compared to non-fatal IDOs, fatal cases were more often male (55.2% vs. 42.0%), older in age (median 44 vs. 35 years), and more frequently involved multiple drugs (78.3% vs. 48.5%),” says the study.
According to the research, certain classes of antidepressants were associated with a 15-fold increased risk of death and other painkillers with a 12-fold increased risk. It states: “Clinicians need to consider the case fatality risk of drugs when determining treatment for patients at risk of or those who have previously harmed themselves.”
The authors said they understood it is the first study which estimated case fatality risk associated with IDOs involving multiple drug types, and added that, given the risks of fatal overdose which are associated with certain antidepressants, “action in addition to recommendations is perhaps needed in order to protect patients at risk of overdosing with these drugs”.
“Prescribers should remain cognisant of the medication load of older patients and monitor for and respond to indicators of drug misuse within this subgroup.
In particular, prescribing of drugs including those with established toxicity, should be reviewed before long term-use is established to ensure patient safety in which the therapeutic effects are balanced against the risk of potential harm from such drugs.
According to the research paper, as the fatality of an IDO increases significantly as the number of drugs used in combination increases, it indicated the importance of restricting or avoiding multiple drug prescribing, when possible.
The study states: “As successful suicide prevention required multiple level interventions, such means restriction measures should also be accompanied by treatments at individual level, to be provided by the mental health and allied services, including patient education, effective pharmacological and psychological treatments.”
