Mental illness constitutes 13 per cent of the global burden of disease (Collins et al., 2011). It is often treated in family care with either pharmacological or psychosocial interventions (e.g., psychotherapy, family support, alternative therapies) or a combination of both. To date, however, pharmacotherapy remains the best studied and evidenced treatment for many mental illnesses, as well as being the most cost-effective.
Pharmacotherapy of Depression
Selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs) are used as first-line antidepressants because they are safer and more tolerable than first-generation antidepressants such as tricyclic antidepressants (TCAs) and monoamine oxidase inhibitors (MAOIs) (Lam et al., 2009). The SSRIs citalopram (Celexa), escitalopram (Cipralex), fluoxetine (Prozac) fluvoxamine (Luvox), paroxetine (Paxil) and sertraline (Zoloft); the SNRIs venlafaxine XR (Effexor) and desvenlafaxine (Pristiq); and the dual action antidepressants bupropion (Wellbutrin) and mirtazapine (Remeron) are some of the first-line options for treating major depression, based on efficacy and tolerability studies (Lam et al., 2009). Escitalopram and sertraline have been recommended as offering the best acceptability and efficacy for the acute treatment of depression, with sertraline being the most cost-effective in many countries (Cipriani et al., 2009).
TCAs and some atypical antipsychotics, such as quetiapine (Seroquel), and the serotonin antagonist trazodone (Desyrel), are often used as second-line antidepressants because of their lower tolerability and safety, as well as side-effects such as sedation (Lam et al., 2009). MAOIs are reserved as a third-line intervention due to their tolerability and dietary restrictions.
Duration of Treatment
If there is a robust and adequate response to the antidepressant, the Canadian Network for Mood and Anxiety Treatments (CANMAT) guidelines suggest maintenance for at least one year before consideration should be given to tapering or discontinuing the antidepressant. There is evidence suggesting that maintenance treatment can be effective in relapse prevention (Lam et al., 2009). In the case of chronic depression, the antidepressant should be maintained for at least two years. Older age, early onset in life, recurrent episodes, chronic medical conditions, other psychiatric comorbidities and adverse social situations should be considered in relapse prevention. In summary, the choice of antidepressant should be individualized, taking into consideration efficacy and tolerability and using switching and augmentation strategies to optimize response. Escitalopram and sertraline appear to offer the best tolerability and efficacy of the SSRIs. Sertraline is the most cost-effective for the acute treatment of depression (Lam et al., 2009).
Pharmacotherapy of Bipolar Disorder
Treatment goals in bipolar disorder include suppressing acute mania and managing acute depression, preventing suicide, decreasing the number and severity of episodes, improving client functioning between episodes and protecting from relapse (prophylaxis and maintenance treatments). Often, a single medication may not be able to treat all these facets of the disorder. Clients need a safe and rational combination of regimens.
Although pharmacotherapy forms the cornerstone of management, CANMAT guidelines suggest that using adjunctive psychosocial treatments, educating clients and families and incorporating a chronic disease management model involving a health care team are required in order to provide optimal management for clients with bipolar disorder (Yatham et al., 2009).
Medications commonly used in the management of bipolar disorder include atypical antipsychotics (e.g., quetiapine, aripiprazone, ziprasidone, olanzapine) and anticonvulsants (e.g., lithium, lamotrigine, divalproex, carbamazepine), with antidepressants (SSRIs, TCAs, MAOIs) used more rarely due to their side-effect profiles.
Pharmacotherapy of Psychosis
When choosing an antipsychotic medication for acute psychosis in schizophrenia, mania and related psychotic disorders, practitioners consider many variables, such as illness type, duration and comorbidity, client characteristics, efficacy, tolerability, pharmacodynamics and pharmacokinetics. While there is considerable debate around the available antipsychotics and their profiles, there is strong agreement about the importance of early intervention. The first-line treatment for many psychotic disorders is antipsychotic medication (oral or intramuscular injection). Sometimes there is a need for hospitalization. While antipsychotics are the most effective treatment for acute psychosis in schizophrenia, mania and related psychotic disorders, psychosocial interventions need to be part of the treatment, in order to optimize the outcome and improve adherence. These pharmacological and social interventions need to be tailored to the individual and the particular phase of the illness (Canadian Psychiatric Association, 2005).
Pharmacotherapy of Addictions
Pharmacotherapy plays a key role in the effective treatment of alcohol and other drug dependence, along with psychological and social interventions. The goals of addiction treatment include detoxification (as a substitute or adjunctive), preventing withdrawal symptoms, reducing cravings, normalizing disrupted physiological function and preventing relapse. The drugs of abuse that have pharmacotherapy options are opioids, stimulants, nicotine and alcohol.
A complete assessment, treatment of intoxication and withdrawal symptoms (where necessary) and addressing comorbid psychiatric and medical problems are all part of a complete treatment plan for clients with substance use problems.