Home > Intentional drug overdose involving pregabalin and gabapentin.

Lyons, Suzi (2018) Intentional drug overdose involving pregabalin and gabapentin. Drugnet Ireland, Issue 65, Spring 2018, p. 18.

PDF (Drugnet Ireland, Issue 65 Spring 2018) - Published Version

This study looked at intentional drug overdoses (IDOs) involving pregabalin and gabapentin that were treated in emergency departments (ED) in Ireland, from 2007 to 2015, as recorded by the National Self-Harm Registry Ireland.1 For more in-depth information on pregabalin and gabapentin (gabapentinoids), see the overview on page 00.


The annual number of IDOs involving gabapentinoids increased year on year from 0.5% in 2007 to 5.5% in 2015. In 2015, there were 369 IDOs involving gabapentinoids, the highest number recorded in the study period. In total, there were 72,391 IDOs between 1 January 2007 and 31 December 2015. Of these, 2,115 (2.9%) were known to involve a gabapentinoid. Pregabalin was involved in 1,953 cases (2.7% of total IDOs; 92.3% of total known gabapentinoid IDO).

Of those IDOs involving gabapentinoids, the majority were women (59.9%), with a median age of 37 years (74.6% were aged 24‒54 years). Over one-half (52.4%) involved multiple drugs, while over one-third (37.2%) involved alcohol.

Compared to those IDOs that did not involve gabapentinoids, the study group was older (median age 37 compared to 32 years); took significantly larger number of tablets (30 compared to 21); had less alcohol involvement (37.2% vs 42.8%); and were more likely to be admitted to hospital (general or psychiatric) (39.1% vs 34.0%).


This large study showed the significant increase over a 10-year period in IDOs presenting to EDs involving gabapentinoids, typically involving more women and those in early/middle age. This increasing trend in the number of IDOs involving gabapentinoids reflects the international evidence. International evidence also shows that women are more likely to attempt an IDO and are more likely to take an antiepileptic (one indication for gabapentinoids) and are more likely to be prescribed an antiepileptic. This may explain why there were more women than men treated for IDOs involving gabapentinoids.

The authors note with concern the involvement of alcohol, even though it was slightly lower for IDOs involving gabapentinoids compared to other drug groups. Evidence shows that involvement of alcohol in an IDO is associated with repeat attempts, impacts on patient treatment and hospital resources. Mixing prescription drugs with alcohol also increases the risk of fatal overdose, particularly as both the gabapentinoids and alcohol are central nervous system depressants. The study also showed that this group was more likely to be admitted to hospital, again mirroring other research that shows that IDOs involving antiepileptics require more intensive medical and psychiatric treatment.

The large number of tablets consumed by this particular group is also worth mentioning. Often cases of larger numbers of tablets taken are associated with higher suicidal intent. However, choice of drug in IDO is mostly determined by availability, so it may be more reflective of prescribing trends.

A number of limitations were highlighted by the authors. The study does not have information on intent, whether it was suicide or misuse. Another limitation is that the numbers of tablets taken were self-reported; however, where possible, the National Self-Harm Registry tries to corroborate information with other sources. It also does not report if any of the study group had a history of misuse of other drugs.

The authors state that this study shows the importance of responsible and vigilant prescribing for all psychotropic drugs, including gabapentinoids, in particular for those with a history of previous IDO and/or a history of drug misuse or dependence.


1    Daly C, Griffin E, Ashcroft DM, Webb RT, Perry IJ and Arensman E (2018) Intentional drug overdose involving pregabalin and gabapentin: findings from the National Self-Harm Registry Ireland, 2007‒2015. Clin Drug Investig, 38(4): 373‒380. https://www.drugsandalcohol.ie/28436/

Item Type
Publication Type
Irish-related, International, Open Access, Article
Drug Type
New psychoactive substance, Prescription/Over the counter
Intervention Type
Harm reduction
Issue Title
Issue 65, Spring 2018
Page Range
p. 18
Health Research Board
Issue 65, Spring 2018
Accession Number
HRB (Electronic Only)

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