Here we describe a 37-year-old man who presented with 20-year history of polydrug dependence, drug-induced psychosis and antisocial personality disorder. He was found to also have a 5-year history of intermittent needle fixation. His injecting behaviour and drug use improved significantly with fluoxetine while being on methadone maintenance.

Needle fixation has been defined by McBride et al¹ as the ‘repetitive puncturing of the skin with or without the injection of psychoactive drugs via intravenous, subcutaneous or intra-muscular routes, irrespective of the drug or drugs injected or the anticipated effects of the drug’.

During the mid 1990s he was using alcohol to a harmful level and had been smoking up to 60 cigarettes per day at the time. He had epileptic seizures probably caused by herpes encephalitis from which he had suffered in his early twenties and for which he was receiving carbamazepine 1200 mg/ day. In 2001, he was diagnosed with hepatitis C for which he had never received any treatment.

At the time of his current presentation, he was under the care of the local Community Mental Health Team. He had received several diagnoses ranging from schizophrenia and mental and behavioural disorder due to multiple substance use over the past 15 years and had been admitted under the Mental Health Act 1983 on several occasions. He had also been diagnosed with antisocial personality disorder and found to have an IQ of 71. His main complaints included second person auditory pseudohallucinations, hearing several voices making derogatory comments and telling him to kill or harm himself. He had made several suicide attempts, including attempted hanging while in prison, taking impulsive overdoses and making lacerations to his wrists. These usually occurred in the context of heavy substance use. He was on weekly 50 mg flupenthixol decanoate intramuscular injections. With regards to current drug use, he was smoking and injecting heroin and crack cocaine. He had been injecting substances into his neck, groin or limbs.

In describing his needle fixation behaviour he reported drawing blood into an empty syringe and re-injecting it many times daily over the previous 8 months. He would use clean equipment each time and inject his own blood for up to 20 times in two2 minutes. He was injecting heroin about twice a week and at other times was injecting water. He had reported similar behaviour occurring intermittently over the past 5–6 years. He injected mostly in the mornings but was unable to identify any precipitating factors. Prior to injecting he described mounting tension and craving for needles, which was released by inserting needles and indulging in the above behaviour. He described this process as more attractive than heroin itself most of the time and would feel intense relief after inserting a needle. As a consequence he had suffered multiple abscesses that had to be treated with antibiotics. He appeared unaware of the risks of his behaviour such as septicaemia, embolism and blood borne viruses. Attempts to distract himself by making tea, listening to music or talking to somebody had little effect.

Pates et al³ studied 19 needle fixated subjects who when compared to 23 non-needle fixated individuals displayed significantly higher scores for sexual arousal and for whom injection had a greater significance than efficient delivery of the drug. Some individuals substituted inert substances for the drug and reported sexual arousal and obsessive compulsive disorder (OCD) symptoms associated with repeated injections.

The concept of needle fixation has been criticised as being a construct subsuming several different injecting behaviours under an elusive and broad definition of needle fixation as the ‘repetitive puncturing of the skin with or without the injection of psychoactive drugs via intravenous, subcutaneous or intra-muscular routes, irrespective of the drug or drugs injected or the anticipated effects of the drug’.⁴

Needle fixation is often missed in patients presenting with intravenous drug use and also seems frequently dismissed by clinicians. However, it is important because of the risks associated with frequent injecting behaviour, including blood borne viruses, septicaemia, thrombosis and abscesses, as well as the negative impact on the prognosis of intravenous drug use.

Several aetiological hypotheses for needle fixation have been postulated, including activation of the opioid system by the inert substance acting as placebo thereby resembling the action of opiates.⁵ Pates et al suggest the ‘rush’ associated with injecting as a perpetuating factor.³

McBride et al proposed that operant and classical conditioning could explain needle fixation.¹ In their study, a high number of individuals reported heightened levels of anxiety prior to injecting and it is thought that the relaxation experienced afterwards reinforces the injecting behaviour. Secondary gains such as sexual pleasure, pain and social status might be linked to operant conditional processes and it appears that other social and environmental processes could also be explained by this model.¹ However, whether learning theories are useful constructs to explain needle fixation remains to be seen.

Fluoxetine, a selective serotonin reuptake inhibitor, is indicated for the treatment of depression and OCD. In animal studies it has been shown that fluoxetine can suppress the development of morphine tolerance and dependence to antinociceptive effects of morphine.⁶ Improvement in ‘needle fixation’ behaviours in our case can be interpreted in this context. It may also be possible that complex inhibitory interactions between serotonergic and dopaminergic pathways in the forebrain have a role to play.⁷ These postulated neuropharmacological actions of fluoxetine may lead to reduction of reward directed behaviours.

At present there is little evidence for any effective treatment strategies or data regarding the prevalence of needle fixation. The current recommended treatment for needle fixation consists of cognitive behavioural therapy combined with cue exposure.³

The likelihood of successfully treating the patient described with a cognitive behavioural therapy based approach would be relatively low due to his borderline IQ, his limited insight into his difficulties and little motivation to change.

Cue exposure consists of presenting the patient with paraphernalia used for injecting either imaginatively or directly and subsequent systematic desensitisation. It is only recommended in conjunction with cognitive behavioural therapy as it might otherwise lead to arousal and further reinforcement of needle fixated behaviour.³

Whether fluoxetine or other psychopharmacological interventions could add anything to the armamentarium currently used to treat needle fixation remains to be seen.