Because the psychopathology of eating disorders is quite broad and severe, involving everything from core fears of obesity, overpriced perceptions of weight and body size, and preoccupation with food, to behavioral compulsions and stereotypes, and emotional anxiety, depression, irritability, and hostility, many psychopharmacological treatments have been used to manage these symptoms in patients with eating disorders.
The available evidence suggests that pharmacotherapy alone is not ideal for treating eating disorders, but can be used as an adjunct to psychotherapy, diet recovery, and treatment of the somatic or psychiatric complications of eating disorders as part of a comprehensive treatment.
Because eating disorders often begin in adolescence and clinicians often need to treat patients from childhood to adulthood, the psychopharmacological treatment section of this guideline provides recommendations for the treatment of anorexia nervosa, bulimia nervosa, and eating disorders not otherwise specified (EDNOS), primarily bulimia, in the adolescent and adult age groups, respectively.
1,Psychopharmacological treatment of anorexia nervosa
The evidence base for the pharmacological treatment of anorexia nervosa is very limited, and there is no clear evidence to date to confirm that medication has a significant improvement in weight gain or core symptoms in patients with anorexia nervosa; therefore, pharmacological treatment is not recommended as a stand-alone or primary treatment for anorexia nervosa.
Psychopharmacological treatment of anorexia nervosa is mainly used to reduce anxiety or emotional symptoms such as irritability and hostility in order to assist in diet recovery and psychotherapy or to alleviate related complications. Medication should be used with caution in the management of complications of depression, anxiety, or obsessive-compulsive features in patients with anorexia nervosa, as these complications may be relieved by weight gain alone. If bulimia, depression, anxiety or obsessive-compulsive symptoms persist in patients with anorexia nervosa after weight restoration, the use of anti-anxiety and depression medications may be considered.
The current randomized controlled trials (RCTs) investigating the pharmacological treatment of anorexia nervosa have mainly focused on adult patients with anorexia nervosa, and there are no randomized controlled studies on the efficacy of psychotropic medications for minor patients with anorexia nervosa.
When using medications to treat patients with anorexia nervosa, careful consideration should be given to the adverse effects of medication, especially cardiac adverse effects. Drugs that may impair cardiac function should be avoided in patients with anorexia nervosa who are at risk for cardiac complications; if they must be used, cardiac monitoring should be performed. In addition, bupropion has been reported to cause increased seizures in patients with bulimia nervosa, so it is not recommended for use in patients with anorexia nervosa, especially those with bulimic symptoms.
Although no drug trials have been conducted to systematically compare the efficacy of antidepressants other than SSRIs [e.g., TCAs, monoamine oxidase inhibitors (MA0Is), etc.] in patients with anorexia nervosa, these antidepressants should be avoided because they are more likely to cause adverse effects in patients with malnutrition. In the absence of contraindications to the use of selective serotonin reuptake inhibitors (SSRIs), SSRIs should be used as much as possible. When administering medications to patients with anorexia nervosa, patients and families should be warned about the risk of adverse drug reactions.
Second-generation antipsychotics, particularly olanzapine, risperidone, quetiapine, and aripiprazole, have been used in a small number of cases, and research evidence suggests that these drugs may be effective in patients who require severe and relentless resistance to weight gain and who have severe obsessive-compulsive thoughts and delusional beliefs. Although second-generation antipsychotics have fewer adverse effects than the first-generation cone system, patients with debilitating anorexia nervosa may be at higher than expected risk of these adverse effects. Therefore, careful monitoring of patients for extrapyramidal symptoms and sedentary inability is recommended if these medications are used, as well as routine monitoring for potential adverse effects of these medications.
Psychotropic medications for adult patients with anorexia nervosa
1) SSRIs: Because patients with anorexia nervosa often have obsessive-compulsive, depressive, and anxiety symptoms, SSRIs are used clinically to treat patients with anorexia nervosa. It should be noted, however, that most of these symptoms may be a direct effect of the starvation state and may improve when the nutritional status of the anorexic patient improves. Therefore, it is generally not advisable to diagnose psychiatric co-morbidity in patients with anorexia nervosa who are underweight, and there is no need to use SSRIs to control these symptoms. Studies have shown that SSRIs have not been shown to be more effective than placebo in terms of weight, eating, and mood in underweight patients with anorexia nervosa.
In a placebo-controlled study, fluoxetine helped reduce relapse, maintain weight, and reduce obsessive-compulsive and depressive symptoms in weight-restored patients with anorexia nervosa. However, in another placebo-controlled study, fluoxetine did not further reduce relapse rates after weight restoration in patients with anorexia nervosa who were also receiving cognitive-behavioral therapy.
Because of the high case shedding rates in all of these studies, further research is needed to determine whether fluoxetine can prevent relapse of anorexia nervosa. According to the above studies, the main adverse effects of fluoxetine in patients with anorexia nervosa are insomnia, agitation, blurred vision, suicide attempts and possible abuse of the drug by patients to promote weight loss.
Both citalopram and sertraline have been studied in small samples and may have some efficacy in patients with anorexia nervosa. Studies have shown that citalopram (20 mg/d) did not contribute to weight gain in adult anorexic patients with low body weight, but depression, obsessive-compulsive symptoms, and impulsive behavior improved significantly after 3 months of use. Sertraline (100 mg/d) showed some advantages in improving treatment compliance and weight gain compared with placebo.
Precautions for the use of SSRIs in patients with anorexia nervosa: In addition to the usual contraindications, the drug is usually taken after breakfast to reduce irritation of the gastrointestinal tract. Because malnourished patients tend to be more sensitive to the adverse effects of SSRIs, the use of SSRIs in patients with anorexia nervosa should be started from the smallest dose and the dose should be increased slowly.
2) Noradrenergic and specific serotonergic antidepressants (NaSSA): A controlled study showed that mirtazapine appeared to be better than SSR in promoting weight recovery and better than SSRIS in compliance, but not in improving depression and anxiety symptoms. There was no significant difference with SSRIS. Because this drug may cause neutropenia and because patients with anorexia nervosa are at risk of hematocrit due to malnutrition, it is not recommended as a first-line treatment for anorexia nervosa.
3) tricyclic antidepressants (TCAs): clinical trials of amitriptyline (50 mg every other day up to a maximum dose of 3 mg) suggest that it has some advantages in improving bulimic symptoms and promoting weight recovery in patients with anorexia nervosa, but it can cause many adverse effects in underweight patients, including drowsiness, Dry mouth, constipation, hypotension, tachycardia, blurred vision, urinary retention, and leukopenia. Because of the risk of hypotension and arrhythmias, especially prolonged QT interval, TCAs are recommended to be avoided in patients with anorexia nervosa, especially those who are underweight, have purging behavior, or are at risk of suicide.
1) Olanzapine: Studies have shown that small doses of olanzapine (5-10 mg/d) can promote weight gain in patients with anorexia nervosa and improve symptoms related to depression, anxiety, obsessive-compulsive and aggressive tendencies.
2) Quetiapine: An open study suggests that quetiapine can help reduce obsessive thinking and depression associated with eating in patients with anorexia nervosa, but it is less effective in weight gain.
3) Risperidone: There are individual case studies suggesting that risperidone has some efficacy on eating attitudes, cognitive biases, agitation and aggression in patients with anorexia nervosa.
4) Haloperidol: An open study with a small sample found that small doses of haloperidol (1-2 mg) were effective in promoting weight gain and improving self-awareness in patients with anorexia nervosa who were on a strict diet.
5) Other antipsychotics: Chlorpromazine has been used in early studies to promote weight gain in patients with anorexia nervosa, but its efficacy has not been supported by subsequent studies, and because it is prone to hypotension and gastrointestinal adverse effects, it should not be used in patients with anorexia nervosa who are particularly susceptible to these adverse effects.
Because the efficacy of ziprasidone in patients with anorexia nervosa has not been studied and may cause prolongation of the QT interval, it should not be used in patients with low body weight or electrolyte disturbances. In a double-blind controlled study of pimozide and sulpiride, these two drugs did not show better efficacy than placebo in patients with anorexia nervosa.
6) Precautions for the use of antipsychotics: Before using antipsychotics, patients should be informed of the possibility of insulin resistance, hyperlipidemia and prolonged QT interval. Blood biochemistry should be routinely monitored during administration, and adverse reactions should be managed promptly. Although second-generation antipsychotics are associated with fewer extrapyramidal adverse effects than first-generation drugs, the risk of these adverse effects may be higher than expected in debilitated patients with anorexia nervosa.
Therefore, careful testing of patients for extrapyramidal symptoms and sedentary inability is recommended if these medications are used. In addition, the adverse effects of weight gain with second-generation antipsychotics often lead to noncompliance in patients with anorexia nervosa who resist weight gain and should be given special clinical attention.
(3) Other psychiatric drugs
1) Anxiolytics: Because patients with anorexia nervosa often have severe anxiety about eating, the use of anxiolytics before meals may help to reduce anticipatory anxiety about eating and improve compliance with eating resumption, despite the lack of evidence to support this. For example, in patients with anorexia nervosa who have severe eating anxiety, 0.25-0.50 mg of lorazepam 20-40 mn before a meal may help to reduce anxiety and assist in eating recovery. Because patients with eating disorders tend to form dependence on benzodiazepines, they should not be used for a long time in patients with anorexia nervosa in order to avoid drug dependence.
2) Other drugs: clinical studies have been conducted on cycloheximide (32 mg/d), colistin, tetrahydrocannabinol (2.5 mg, 2 times/day), lithium carbonate, etc., and no consistent positive results have been found in promoting active eating and weight gain in patients with anorexia nervosa. Strict risk precautions are needed to avoid damage caused by adverse drug effects.