Pharmacological treatment of personality disorder

Pharmacotherapy has a limited role in the primary treatment personality disorder; psychosocial interventions are the core treatment. However, pharmacotherapy may be considered to target specific symptoms when these are severe, cause significant functional impairment or distress, or have not been adequately addressed with psychosocial interventions—there is an absence of high-quality evidence of efficacy. Consider that patients often seek treatment when they are at their lowest ebb. Although clinicians may feel pressured by the patient to use pharmacotherapy, or compelled by a sense that alternatives are lacking, pharmacotherapy is not first line.

Note: Pharmacotherapy has a limited role in personality disorder; psychosocial interventions are the core treatment.

Symptoms of personality disorder that pharmacotherapy may be used to target are:

  • cognitive-perceptual symptoms—paranoia, hallucinations
  • impulsive-behavioural dyscontrol—self-injury, interpersonal aggression
  • affective dysregulation—dysphoric mood, mood lability, anxiety, anger.

Before considering pharmacotherapy to target symptom(s) of personality disorder, consider if the symptom(s) could be caused by a co-occurring psychiatric disorder; for example:

If a co-occurring psychiatric disorder is diagnosed, its management may include pharmacotherapy. If the target symptom(s) are not better explained by a co-occurring psychiatric disorder, use psychosocial interventions first line and only consider adjunctive pharmacotherapy.

If considering pharmacotherapy to target symptom(s) of personality disorder, use shared decision making with the patient, and discuss the potential benefits and harms of pharmacotherapy. Consider the risk of drug dependence, abuse and overdose, and whether adherence to treatment may be an issue. Avoid using a drug that can be fatal in overdose because there is a high risk of overdose with prescribed drugs in people with severe personality disorder. Avoid using a drug to treat personality disorder in the perinatal period—see Considerations in managing personality disorder in the perinatal period. If a drug is required, see Principles of psychotropic use during pregnancy and Principles of psychotropic use while breastfeeding for considerations.

Before trialling a drug, the patient and prescriber should discuss and reach agreement on the parameters of the trial, including the target symptom(s), how the patient’s response to the drug will be monitored and measured, and the expected duration of treatment.

If pharmacotherapy is used to target symptom(s) of personality disorder, choose a drug that is expected to have efficacy against the target symptom(s) and consider seeking advice from a psychiatrist. If response to the drug is inadequate, withdraw the drug and consider alternate treatment options (either psychosocial or pharmacological). If using a second (or subsequent) drug, use sequential monotherapy—avoid polypharmacy, which is common among people with severe personality disorder.

Despite the widespread use of selective serotonin reuptake inhibitors (SSRIs), evidence does not support their use for dysphoric mood or mood lability caused by personality disorder. Anxiety is a common reason for patients with personality disorder to seek treatment and can cause significant distress. Anxiety as a symptom of personality disorder should be managed in the same way as generalised anxiety disorder. Treatment of anxiety may involve use of an antidepressant for maintenance therapy, or short-term use of a benzodiazepine for anxiety that is severe and disabling, or causing the patient unacceptable distress.

For cognitive-perceptual symptoms, the evidence for pharmacotherapy is unclear. Antipsychotics may have some effect on specific cognitive-perceptual symptoms, but there are no randomised controlled trials of antipsychotics for hallucinations caused by personality disorder. Antipsychotics can cause serious adverse effects, and are associated with abuse. Quetiapine, in particular, is associated with problem use and overdose and, as such, is subject to monitoring by drug diversion monitoring systems in some Australian states. If considering pharmacotherapy for severe or persistent cognitive-perceptual symptoms, seek advice from a psychiatrist.

There is very limited evidence for pharmacotherapy for impulsive-behavioural dyscontrol—seek advice from a psychiatrist before considering pharmacotherapy.

People with personality disorder often present during an acute crisis. Patients usually respond well to being given support and time to talk about their concerns—follow the key principles for working with a patient with personality disorder. Use simple problem-solving strategies to address immediate precipitants and involve the patient’s family, carers or significant others if possible. If these strategies are insufficient to manage the acute crisis, consider using adjunctive short-term pharmacotherapy, with a limited supply of medication, such as:

If a drug is used short term, ensure the patient understands the intended duration of treatment—stop the drug once the acute crisis is resolved.

Note: Stop short-term pharmacotherapy once the acute crisis is resolved.

Using the above principles for managing personality disorder will often prevent acute agitation or behavioural disturbance. However, if symptoms of personality disorder are so severe that the patient is acutely agitated or has an acute behavioural disturbance, do not start treatment before determining that it is safe and appropriate to intervene. If possible, use nonpharmacological measures, including verbal de-escalation and psychological intervention, to reduce the risk of harm. If the patient remains acutely agitated or at risk of harming themselves or others, see Pharmacological management for acute behavioural disturbance in adults or Pharmacological management for acute behavioural disturbance in older people for advice on drug therapy.