Risperidone (Risperdal®)

This article provides a comprehensive overview of risperidone, including how it works, the conditions it treats, side effects, interactions, and precautions.

Key Takeaways:

• Risperidone is an atypical antipsychotic medication that helps balance levels of serotonin and dopamine. It is approved to treat schizophrenia, as well as certain forms of bipolar disorder and autism.

• Common side effects of risperidone include sleepiness, headache, and mood changes. There is a chance of serious side effects, such as an increased risk of metabolic syndrome, heart rhythm changes, and extrapyramidal symptoms (such as tremors or muscle rigidity).

• Risperidone may interact with many other mental health medications, as well as drugs and alcohol. Your doctor will determine if risperidone is right for you.

Understanding Risperidone

Risperidone is a second-generation (or atypical) antipsychotic. It was initially approved for use in the United States in 1993. It is primarily used for schizophrenia, bipolar disorder, and irritability within autism. Risperidone is only available as a prescription. ^[1]

Like other atypical antipsychotics, risperidone has a generally lower risk of motor-related side effects, including extrapyramidal symptoms, when compared to first-generation (or typical) antipsychotics.

How Risperidone Works

Risperidone primarily works by affecting the levels of serotonin and dopamine in the brain. These two are both important neurotransmitters involved in a variety of mental functions and other functions. The effects on serotonin are thought to improve mood and reduce depression, while the blocking effects on dopamine receptors may help control symptoms of schizophrenia (e.g., hallucinations, delusions), as well as mania and agitation. ^{[1] [2]}

Brand Names

There are several brand names for risperidone, which differ in their specific formulation: ^[2]

• Risperdal®:

• Oral tablet

• Oral solution

• Risperdal Consta®

• Extended-release injectable suspension

• Perseris®

• Extended-release injectable suspension

• Uzedy®

• Extended-release injectable suspension

Conditions Risperidone is Used For

There are several research-backed risperidone uses. Risperidone is FDA-approved to treat the following conditions: ^[1]

• Schizophrenia (in adults and children 13 and older)

• Acute manic or mixed episodes within bipolar I disorder (adults and children 10 and older)

• Irritability within Autism (in children ages 5 to 16)

Within schizophrenia, risperidone can help control both positive and negative symptoms. Positive symptoms include hallucinations, delusions, and disorganized thoughts, while negative symptoms include lack of motivation, social withdrawal, and trouble thinking clearly. ^[2]

Within bipolar disorder, risperidone can help contribute to more balanced moods and reduce the severity of mood swings. It is particularly useful for acute mania and agitation. ^[1]

Regarding autism, risperidone is known to help with a variety of emotional and behavioral issues, including irritability, aggression, self-injury, and rapid mood changes. ^[3]

In addition to these conditions, risperidone is sometimes used off-label for certain conditions, including:

• General psychotic symptoms

• Borderline personality disorder

• Delusional disorder

• Delirium

• Depression

• Various brain injuries

• Post-traumatic stress disorder

• Conduct disorder

• Lesch-Nyhan syndrome

• Tourette syndrome

• Trichotillomania

• Speech disorders, such as stuttering

• Movement disorders

• Developmental disorder

• Aggression and agitation within dementia

• Other features of autism:

• Social impairment

• Hyperactivity

• Stereotypical behaviors

• Cognitive issues

Risperidone Side Effects

There are numerous possible side effects with risperidone. Some side effects may get better or resolve completely over time as your body adjusts to the medication, while other side effects may persist with continued use. It’s important to talk to your doctor about any side effects you experience, so they can adjust your treatment as needed.

The most common risperidone side effects are: ^{[2] [4]}

• Sleepiness/somnolence

• Insomnia

• Agitation

• Anxiety

• Headache

• Fatigue

• Parkinsonism

• Runny or stuffy nose

• Increased appetite

• Vomiting

• Tremor

• Urinary incontinence

Other relatively common side effects that may occur with risperidone include: ^{[2] [3] [4] [5]}

• Constipation

• Weight gain

• Nausea

• Stomach pain

• Heartburn

• Dry mouth

• Increased saliva

• Restlessness

• Decreased sexual ability/function

• Back, muscle, or joint pain

• Fever

Dangerous and Rare Side Effects

Some risperidone side effects can be dangerous or life-threatening. While rare, it’s essential to talk to your doctor or whoever prescribed your medication if you notice any of the following severe side effects: ^{[1] [2] [3] [5]}

• Increased prolactin. This can lead to various issues, including:

• Women losing their periods.

• Unexpected breast growth and/or breast discharge.

• Decrease in libido, ability to orgasm, and other sexual functions.

• Allergic reactions (e.g rash, itching, hives, swelling of the face, lips, or throat).

• Metabolic abnormalities, such as high blood sugar, high cholesterol, and high triglycerides.

• Neuroleptic malignant syndrome: This is a dangerous and potentially life-threatening condition involving:

• High fever

• Stiff muscles

• High blood pressure

• Increased sweating

• Fast or irregular heartbeat

• Confusion

• Low blood pressure, including orthostatic hypotension. Symptoms may include:

• Dizziness

• Feeling faint or lightheaded

• Fainting

• Seizures

• Prolonged or painful erections

• Significant changes in mental status, including:

• New or worsening depression

• Thoughts of suicide or self-harm

• Signs of infection, such as cough, chills, or sore throat

• Stroke

• Tardive dyskinesia: This involves involuntary movements of the torso, neck, head, and limbs (often affecting the tongue and lips)

• If this develops, it may be permanent even after risperidone is discontinued

• Heart rhythm changes, which can also lead to sudden cardiac death

• Changes in temperature regulation, especially in hot environments or when exercising a lot

This list may not contain all possible side effects.

Precautions

Risperidone is contraindicated for anyone with a known allergy or hypersensitivity to it. It may also be problematic for individuals with hallucinogen-persisting perception disorder (HPDD) due to its potential to exacerbate panic and visual symptoms, more studies are needed to better understand its effects on this condition. ^[1]

Many health conditions and symptoms may pose a greater risk of side effects when using risperidone. It’s important to tell your doctor if you have any health conditions, especially: ^{[1] [3]}

• Parkinson’s disease.

• Dyslipidemia.

• Low white blood cell count.

• Difficulty swallowing.

• Trouble with balance.

• Breast cancer.

• Osteoporosis.

• Chest pain.

• High or low blood pressure.

• Irregular heartbeat.

• Heart attack or heart failure.

• Stroke.

• Seizures.

• Heart, kidney, or liver disease.

• Diabetes.

• Phenylketonuria.

Considerations and Risks

Older adults with dementia have an increased risk of stroke and death when taking risperidone. Most of these deaths were cardiovascular or infectious in nature. ^{[1] [4]}

Risperidone may cause extrapyramidal or withdrawal symptoms in newborns, especially when it is used during the third trimester. Use during pregnancy is dependent on a careful analysis of risks to benefits. In addition, risperidone can be excreted into breast milk, so caution is advised for breastfeeding women. ^{[1] [2]}

Risperidone can cause drowsiness, which may affect your ability to drive, operate machinery, react quickly, and perform any complex mental or physical tasks. Do not engage in any of these activities until you know how risperidone affects you and you receive your doctor’s approval. ^[3]

Risperidone Interactions

Risperidone may interact with a variety of medications, drugs, and other substances. Listed below are some of the more significant risperidone interactions: ^{[1] [2] [4] [5] [6]}

• Selective-serotonin reuptake inhibitors (SSRIs) (e.g. fluoxetine, paroxetine)

• Various antidepressants (e.g. bupropion, amitriptyline)

• Central nervous system stimulants (e.g. methylphenidate)

• Medications for anxiety or sleep, such as:

• Benzodiazepines (e.g. alprazolam)

• Non-benzodiazepine sedative-hypnotics (e.g. zopiclone, eszopiclone in the US)

• Opioids (e.g. morphine, tramadol)

• Antihistamines for allergies, cough, and cold (e.g. cetirizine, diphenhydramine)

• Levodopa and other dopamine agonists (e.g. bromocriptine)

• Medications for blood pressure (e.g. propranolol)

• Other antipsychotics (e.g. thioridazine, pimozide, clozapine)

• Anti-arrhythmic medications (e.g. quinidine)

• Certain antibiotics, such as rifampin

• Anti-seizure medications (e.g. carbamazepine)

• Diuretics (e.g. furosemide)

Combining risperidone with alcohol or recreational drugs may exacerbate drowsiness and other side effects. Avoid any of these combinations.

Risperidone may also interact with St. John’s wort and ginkgo biloba. The effects on other herbs and supplements are generally unknown. ^[6]

As always, tell your doctor everything you take or have taken, including prescription and over-the-counter medicines, herbs, vitamins, and supplements.

Risperidone Dosage

Risperidone is often used orally in the form of tablets, a solution, or dissolvable tablets. In addition, risperidone is available as an extended-release injection, which can be delivered intramuscularly or subcutaneously. ^[1]

Listed below are the general dosage guidelines for risperidone: ^{[1] [4]}

• Schizophrenia:

• Oral: 1 to 4 mg per day, in one or two doses

• Subcutaneous: 90 to 120 mg once monthly (Perseris®); 50 to 125 mg once monthly (Uzedy®)

• Intramuscular: 25 to 50 mg every 2 weeks

• Bipolar I disorder with acute manic or mixed episodes:

• 1 to 6 mg orally, once daily or divided into two doses

• Tourette syndrome (off-label):

• 0.2 to 3 mg orally, once daily or divided into two doses

The exact dose of risperidone for other conditions is not as clearly defined. Your doctor will determine the appropriate dose of risperidone for your individual situation and condition.

What to Do in the Event of an Overdose

An overdose on risperidone is typically not fatal, but it can still be dangerous and requires prompt attention.

If an overdose is suspected, contact your poison control center or a medical toxicologist right away. In severe cases, contact 911 or your local emergency number.

Symptoms of risperidone overdose often involve more severe forms of common side effects, including: ^{[1] [3]}

• Drowsiness

• Sedation

• Rapid heart rate

• Low blood pressure

• Extrapyramidal symptoms

Severe cases can lead to seizures and heart rhythm abnormalities.