Pregabalin dependence with pregabalin induced intentional self-harm behavior: A case report.

Sir,

Pregabalin is a novel gamma amino butyric acid (GABA) analogue which is used for neuropathic pain and partial onset seizures.[12] Drug enforcement agency has categorized pregabalin as a schedule V drug under the terms of controlled substances act. In 2008, US Food and Drug Administration announced a class warning regarding increased risk of suicidality in patients on pregabalin with epilepsy and psychiatric disorders.[3] This case report describes a case of pregabalin dependence with pregabalin induced intentional self-harm behavior.

A 30-year-old married male was brought by his mother with a history of pregabalin dependence since 4 years. Patient was started on 75 mg of pregabalin for neuropathic pain in temporomandibular joint. As he experienced euphoria and increased energy levels after pregabalin consumption, his consumption increased to 20 capsules (equivalent to 1500 mg) at irregular intervals per day over the period of 1 year and since last 2 years his consumption increased to 40 capsules (equivalent to 3000 mg) per day due to tolerance to pregabalin. He would experience withdrawal symptoms such as palpitations, restlessness, and dysphoria on missing the doses.

After continuous use of 3 years of pregabalin, patient attempted suicide by consuming organophosphorus compound on two occasions. There was no antecedent life event stressor. He had no past or family history of psychiatric illness or drug seeking behavior.

On admission, mental status examination revealed that he was conscious, oriented with dysphoric mood, anxious affect, ideas of worthlessness and passive suicidal ideations. He was in the action stage of motivation that means he chose a strategy for change to remain abstinent from pregabalin and pursued it.

His diagnosis according to International Classification of Disease-10 criteria is mental and behavioral disorders due to use of pregabalin, independence, currently in uncomplicated withdrawal with intentional self-poisoning (F19.20, 19.30, X68).

On admission, his HAM A score was 19/56 HAM D score was 30/64, Beck suicide intent scale was 7/40.

He was started on equivalent dose of pregabalin and gradually 75 mg of pregabalin was tapered on every alternate day. He was given antidepressants and motivational enhancement therapy and was successfully detoxified over a period of 2 months.

Although, pregabalin has been labeled a schedule V drug (lowest abuse potential), our patient in the absence of any family or prior history of drug seeking behavior developed pregabalin dependence. It has stated that the GABAergic effects due to pregabalin may cause positive reinforcement leading to abuse potential in some patients.[14]

Tandon et al. in 2013 reported a case of pregabalin induced self-inflicted multiple injuries over forearm after continuous use of pregabalin.[5] The probable mechanism explained for the self-harm behavior is reduction of serotonin by pregabalin.

Thus, our case highlights the abuse potential of pregabalin and risk of self-harm behavior with its continuous use. It has the implication for the pregabalin use in pain disorders Hence, we recommend all clinicians to remain vigilant and mindful of the potential for abuse or dependence of pregabalin, while prescribing it for the patients, irrespective of their drug seeking behavior.