From pills to pillars: Medications in eating disorders and building a strong foundation for recovery

Presented by Dr. Sam S. Moss, MD

There are currently only two medications that are FDA-approved for the treatment of eating disorders: Fluoxetine (Prozac) for bulimia nervosa and Lisdexamfetamine (Vyvanse) for binge eating disorder. With eating disorders affecting 9% of the US population at some point in their lifetime,1 why are so few medications approved for treatment?

One possible reason is how Federal research dollars are being allocated. For example, Federal support for schizophrenia works out at $86.97 per individual, and for autism, it is $58.65 per individual. By contrast, for eating disorders, this figure is just $0.73 per affected individual.

This is not to say that autism and schizophrenia research doesn’t require the funding it receives. These figures simply highlight the “lack of attention” eating disorder research receives from the Federal Government. While these are U.S. figures, these numbers are mirrored across the globe. 

The figures also illustrate the significant gap between the public health burden of eating disorders and the current state of research to investigate novel treatments. 

In this article, we look at the use of medications in eating disorders in the treatment of co-occurring disorders, as well as clinical considerations that should be made and personalizing treatment to the client. 

Introduction: History of research into medications for anorexia nervosa

Anorexia nervosa (AN) is a chronic and severe mental illness. It has the highest mortality rate in psychiatry, is associated with frequent relapse, and has a high disease burden and high treatment cost. Despite this, no medication has been approved for the treatment of AN, yet a large proportion of individuals with AN are treated with psychotropic medications. 

The lack of a medication suitable for AN is not from a lack of trying. Since the 1970s, almost every class of medication has undergone a research trial to assess its viability as a treatment for AN, including:

  • Appetite stimulants
  • Antidepressants
  • Dietary supplements
  • Antipsychotics
  • Mood stabilizers
  • The hunger hormone ghrelin

Unfortunately, none have yielded substantial benefits to be recommended for treating AN.

Targeting treatment: Co-occurring conditions

Higher rates of comorbidity often mean greater severity, treatment resistance, and poor outcomes in eating disorders. Common co-occurring conditions include:

Prevalence of co-occurring conditions

Research indicates that 55 to 97% of people diagnosed with an eating disorder also receive a diagnosis for at least one more psychiatric disorder.2

Anxiety disorders

Anxiety disorders are the most commonly occurring mental health disorders in the U.S., and they are also particularly prevalent among those diagnosed with an eating disorder. Research indicates that anxiety disorders are present in:3

Mood disorders

Research shows that eating disorders are deeply connected to mood disorders. One recent large-scale study of 2,400 participants with eating disorders discovered 94% had a co-occurring mood disorder.3 Major depressive disorder is a common mood disorder co-occurring with eating disorders, believed to be suffered by:3

  • 50-70% of those with anorexia nervosa
  • 36-50% of those with bulimia nervosa
  • 33% of those with binge eating disorder

Impulsive control disorders

Impulse control disorders, such as attention-deficit/hyperactivity disorder (ADHD), obsessive compulsive disorder (OCD), and post-traumatic stress disorder (PTSD), often occur alongside eating disorders. 

  • ADHD: Research suggests that adolescent females with ADHD are 3.6 times more likely to develop an eating disorder and almost 6 times more likely to develop bulimia nervosa.4 Plus, the severity of ADHD may predict worse outcomes in eating disorders. 
  • OCD: Studies estimate that between 11 and 69% of people living with an eating disorder also have OCD, while 10-17% of individuals primarily diagnosed with OCD also struggle with disordered eating.5
  • PTSD: Studies have found that, on average, 25% of people with eating disorders experience co-occurring PTSD. Prevalence for PTSD is even higher in those with bulimia nervosa, with studies estimating up to 45% have both disorders.6

Substance use disorders

Substance use disorders and eating disorders co-occur at significantly higher rates than either condition does on its own in the general population. Research shows that up to 50% of individuals struggling with an eating disorder also have issues with substance use.7 Common comorbid substance use disorders include:

  • Cannabis use disorder
  • Stimulant use disorder
  • Tobacco use disorder
  • Benzodiazepine use disorder
  • Alcohol use disorder

Suicide and eating disorders

Suicide rates are also higher amongst those living with eating disorders than in the general population. Individuals with anorexia are 18 times more likely to die by suicide, and those struggling with bulimia are 7 times more likely.8

Medications: Indications and other considerations

Five classes of psychotropic medications can be used in the treatment of co-occurring psychiatric disorders:

  1. Antidepressants: Such as selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), atypicals, serotonin modulators, tricyclic antidepressants (TCAs), and monoamine oxidase inhibitors (MAOIs).
  2. Antipsychotics: Both 1st generation and 2nd generation.
  3. Mood stabilizers: Such as anticonvulsants and lithium.
  4. Anxiolytics: Including benzodiazepines, Buspirone, and beta blockers.
  5. Stimulants: Including methylphenidates and amphetamines.

Treatment of co-occurring anxiety disorders

The first line of treatment for co-occurring anxiety disorders is SSRIs, used in combination with therapy, typically cognitive behavioral therapy (CBT). Examples of SSRIs include:

  • Fluoxetine (Prozac)
  • Sertraline (Zoloft)
  • Paroxetine (Paxil)
  • Citalopram (Celexa)

SNRIs are sometimes used interchangeably with SSRIs but are associated with slightly higher side effects. Examples of SNRIs include:

  • Venlafaxine (Effexor)
  • Duloxetine (Cymbalta)
  • Desvenlafaxine (Pristiq)

How do SSRIs work?

Due to the complexity of the brain, the exact mechanism of action of SSRIs is unclear. It is hypothesized that SSRIs increase the availability of serotonin, which is thought to positively influence mood, emotions, and sleep. 

After carrying a message, serotonin is usually reabsorbed by the nerve cells. SSRIs work by blocking the reabsorption (reuptake) of serotonin at the synapse, meaning more serotonin is available to pass further messages between nearby nerve cells.9 It typically takes 4-6 weeks before the effects of SSRIs are felt, but it can take longer. 

Most people will only experience a few mild side effects when taking SSRIs, which generally improve with time. Common side effects of SSRIs include:9

  • Gastrointestinal distress, such as diarrhea, nausea, and vomiting
  • Sexual dysfunction, including loss of libido, difficulty achieving orgasm, and problems maintaining an erection.
  • Blurred vision, dizziness, and headaches

Other medications for the treatment of co-occurring anxiety disorders

Other medications that can be used for the treatment of co-occurring anxiety include, but are not limited to:

  • Benzodiazepines: Controlled medications that modulate GABA. They are not prescribed as much as SSRIs as they have significant side effects, such as sedation and disinhibition, and it’s habit-forming. Examples of benzodiazepines include Lorazepam, Clonazepam, and Alprazolam.
  • Buspirone (Buspar): A serotonin agonist with minimal side effects; however, it can be “hit or miss” in terms of treatment.
  • Antihistamines: Advantageous in that they don’t need to be taken daily, just as needed. However, they can have a sedating effect and as an appetite stimulant. Examples of antihistamines include Hydroxyzine and Diphenhydramine (Benadryl).
  • Gabapentin and Pregabalin: Used for the treatment of anxiety, these are typically anticonvulsant medications that decrease abnormal excitation in the brain via their action on the calcium channels. 
  • Beta-blockers: Address the physical aspects of anxiety, which can be used on a day-to-day basis by those who have failed with other classes of anti-anxiety medications. Beta-blockers can have a significant impact on heart rate and blood pressure, potentially exacerbating bradycardia and hypotension in those with anorexia nervosa. Examples of beta-blockers include Propranolol and Clonidine.
  • Antipsychotics: Have a profile similar to antihistamines, which helps explain their success in anxiety management. This class of medication is associated with metabolic side effects, including an increased risk of metabolic syndrome. Examples of antipsychotics include Queruapine (Seroquel) and Olanzapine (Zyprexa)
  • Tricyclic antidepressants (TCAs) and monoamine oxidase inhibitors (MAOIs): Older classes of antidepressant drugs that are seldom used these days due to their increased severity of side effects and lethality. 

Treatment of co-occurring mood disorders

Treatment of co-occurring depression
Treatment of co-occurring mania

Treatment of co-occurring psychosis

Medications for co-occurring psychosis are used to treat and manage the symptoms of bipolar disorder, schizophrenia/schizoaffective disorders, major depressive disorder, OCD, bipolar disorder, and substance-induced symptoms. Antipsychotic medications may also reduce eating disorder ruminations and compulsions. 

There are two main classes of antipsychotic medications, both of which have a length of onset of just a few hours:

  • First generation: They work by inhibiting dopamine transmission by blocking dopamine receptors in the brain. They also have histamine, noradrenaline, and choline-blocking action.10 Examples of first-generation antipsychotics include Chlorpromazine and Haloperidol.
  • Second generation: They also block dopamine neurotransmission and serotonin receptor antagonism.10 Examples of second-generation antipsychotics include Risperidone and Olanzapine. 

Treatment of co-occurring ADHD

Due to the clinical considerations of ADHD medications, it’s important to screen for eating disorders before treating ADHD. There are two classes of medications used to treat co-occurring ADHD:

  • Stimulants: This class of drug can act as an appetite suppressant, meaning it may be best to halt stimulant medications during eating disorder treatment and resume after weight restoration. Stimulants can also potentially contribute to anxiety and increase cardiovascular risk. Examples include Methylphenidate, Mixed Amphetamine Salts, and Vyvanse.
  • Non-stimulants: While not as powerful as stimulants, non-stimulants have the advantage that they’re not controlled medications. Examples include Clonidine, Qelbree, and Atomoxetine, the latter of which may cause significant appetite suppression.

Psychiatric medications that impact weight and appetite

Many psychiatric medications can have an impact on appetite and, therefore, may help facilitate eating disorder treatment, as well as address co-occurring psychiatric disorders.

Appetite-suppressant/weight loss
Appetite inducers/weight gain

Universal medical considerations

Whenever an eating disorder patient is prescribed medication for a co-occurring psychiatric disorder, there are considerations to be aware of:

  • Cardiac monitoring is important as certain medications can cause QTc prolongations (i.e., the heart’s electrical system takes longer than usual to recharge between beats) and an increased risk of fatal arrhythmia.
  • The risk of cardiac complications is amplified when there are electrolyte abnormalities caused by purging behaviors, dehydration, restriction, etc.
  • Polypharmacy (taking more than four medications at once) should be avoided to minimize the risk of significant side effects and drug interactions.
  • Consider hepatic or renal function when dosing medications
  • The withdrawal from medications and/or substances of abuse increases the associated risks.

Personalizing treatment: The pill, patient, prescriber, and partnership

There is no one-size-fits-all approach in psychiatry; not every patient will benefit from medications. It’s normal for individuals to be anxious about taking psychiatric medications, particularly for the first time. It’s important to address fears and concerns and answer any questions patients may have. 

How to support the integration of medication

Patient nonadherence to medication is a significant barrier to effective treatment. With ambivalence about taking the medication being the norm and not the exception, creating a good therapeutic alliance between patient and clinician is so important. Other ways to support the integration of medication in treatment are to:

  • Ask the patient if they are taking their medication and identify any barriers, such as fears of dependency or concerns medications may inhibit their emotions. 
  • Troubleshoot challenges to taking medications, such as setting up medication reminders, pill boxes, and routines.
  • Address the side effects of certain medications with adjustments in meal plans.
  • Recognize behavioral and/or physical side effects of medications. 

Personalizing treatment

Family history and genetics can play a role in how an individual will respond to medications. Pharmacogenomic testing provides a metabolic profile for psychotropic medications, which can help guide dosages, as well as give an insight into the severity of potential side effects. 

While pharmacogenetic testing does not determine which medication will work best, it can be helpful for those with an extensive history of medication failures, sensitivities to certain medications, and who have experienced significant side effects. 

Deprescribing

Deprescribing is a phenomenon that arose in the field of child and adolescent psychology, but it also applies well to adults. It involves a structured approach to identify and discontinue medications when risks outweigh potential benefits. 

Before medication is prescribed, there should be a comprehensive psychiatric assessment and review of past psychiatric treatment where possible. Plus, there should be cohesive communication between prescribers to prevent polypharmacy, which can increase the risk and severity of side effects.

Deprescribing should be considered when a medication(s):

  • Doesn’t have a clear indication of use
  • Is ineffective for the symptoms targeted, or symptoms have resolved
  • Is prescribed outside of recommended guidelines
  • Has insufficient benefits to justify side effects
  • Was used as part of a prescribing cascade, i.e., side effects of drugs were misdiagnosed and treated as symptoms of another disorder or drug prescribed to counter side effects of another drug. 

Future directions

So, what is next when it comes to using medications to treat co-occurring disorders in eating disorder clients? There are certainly a lot of challenges, such as:

  • The complex interplay of bio-psycho-social factors
  • The inherent complexity of the brain
  • The “withdrawal” of big pharma from the field, which results in a lack of large-scale research studies
  • The egosyntonic nature of anorexia nervosa, i.e., the lack of motivation for recovery
  • The nutritionally starved brain

Despite these challenges, there are some promising breakthroughs. For example, Olazapine has demonstrated some positive outcomes in weight restoration among patients with anorexia. However, it comes with side effects; the gains can be short-lived, and artificial weight gain can cause weight gain anxiety.

Some additional new drug interventions have shown promise, including:

  • NMDA receptor antagonists such as Ketamine and Esketamine
  • Psilocybin-assisted therapy
  • MDMA-assisted therapy
  • GLP-1 and GLP-2 receptor agonists

Resources

  1. Report: Economic costs of eating disorders. (2021, September 27). STRIPED. Accessed Dec 2023.
  2. Occurring conditions. (n.d.). National Eating Disorders Collaboration. Accessed Dec 2023.
  3. Anxiety, depression, & obsessive compulsive disorder. (2018). National Eating Disorders Association. Accessed Dec 2023.
  4. Biederman, J., Petty, C. R., Monuteaux, M. C., Fried, R., Byrne, D., Mirto, T., Spencer, T., Wilens, T. E., & Faraone, S. V. (2010). Adult psychiatric outcomes of girls with attention deficit hyperactivity disorder: 11-year follow-up in a longitudinal case-control study. The American Journal of Psychiatry, 167(4), 409–417. 
  5. Neziroglu, F., & Sandler, J. (2009). The relationship between eating disorders and OCD part of the spectrum. OCD Newsletter. Accessed Dec 2023
  6. Brewerton, T. (2023, December 12). Eating disorders and posttraumatic stress disorder (PTSD). National Eating Disorders Association. Accessed Dec 2023
  7. Substance use and eating disorders. (2022). National Eating Disorders Association. Accessed Dec 2023.
  8. Book, K. (2023, December 12). The connection between eating disorders and suicide. National Eating Disorders Association. Accessed Dec 2023.
  9. Overview - Selective Serotonin Reuptake inhibitors (SSRIs). (2021). NHS. Accessed Dec 2023.
  10. Chokhawala, K., & Stevens, L. (2023). Antipsychotic medications. In StatPearls [Internet]. StatPearls Publishing.