Risperdal (Risperidone) Side Effects: Common and Rare

Risperdal (risperidone) is an atypical antipsychotic drug approved by the U.S. Food and Drug Administration (FDA) to treat schizophrenia, mania with bipolar I disorder, and irritability in children and adolescents with autism spectrum disorder. It's important to be aware of the potential side effects before starting treatment.

If You Experience Risperidone Side Effects

While many side effects of risperidone are manageable, others may be serious and, in rare cases, life-threatening. Talk to your healthcare provider about any side effects you experience while taking this medication. Seek medical care immediately or call 911 if your side effects are life-threatening.

Overview of Risperidone

Risperdal is a brand name for the generic drug risperidone. It is available in oral tablets, liquid solutions, or injectable suspension forms.

The oral dose of risperidone typically ranges from 1 mg to 6 mg per day, with injectable dosage ranges between 12.5 mg and 50 mg daily. People usually begin at a low dose that is gradually increased until the desired therapeutic effects are achieved.

Several properties of Risperdal can lead to side effects. For instance, it may be sedating due to its antihistaminic properties. As an alpha-adrenergic blocker, it can interfere with hormones that regulate blood flow and blood pressure. Risperidone also has anticholinergic effects that alter the function of smooth muscles in the internal organs.

Common Side Effects of Risperdal

Common side effects of Risperdal, reported in more than 10% of clinical trials, include:

• Abdominal pain or discomfort
• Anxiety
• Constipation
• Cough
• Dizziness
• Drowsiness or sleepiness
• Dry mouth
• Excessive salivation
• Fatigue
• Fever
• Increased appetite
• Involuntary muscle contraction
• Nasal congestion, runny nose, and sneezing
• Nausea and vomiting
• Rash
• Tremors or slow, rigid movements
• Upper respiratory tract infection
• Urinary incontinence

Most of these side effects are mild to moderate in severity.

Extrapyramidal Side Effects of Risperidone

Extrapyramidal side effects (EPS) can affect up to one in four people who take risperidone, although most cases are relatively mild. These side effects affect the central nervous system and cause movement problems.

Types of EPS

• Tardive dyskinesia: A potentially irreversible disorder characterized by involuntary and repetitive movements of the face, mouth, tongue, arms, or legs.
• Akathisia: A feeling of inner restlessness and inability to stay still, often referred to as the "rabbit syndrome."
• Akinesia: A loss or impairment of voluntary movement.
• Dystonic reactions: Intermittent and involuntary contractions of the muscles in the face, neck, trunk, pelvis, and extremities.
• Parkinsonism: A group of neurological disorders that cause movement problems similar to Parkinson's disease, including tremors, slow movement, and stiffness.

Risk Factors

• High dosage of risperidone
• Extended period of treatment with risperidone
• Young adult males
• Organic brain syndromes or intellectual disabilities

It's important to advise your doctor if you experience involuntary muscle movements or have a loss of muscle control while taking Risperdal. Tardive dyskinesia may become permanent if left untreated.

Rare But Serious Side Effects of Risperdal

• Neuroleptic malignant syndrome (NMS): A potentially life-threatening condition characterized by altered mental state, high blood pressure or blood pressure fluctuations, high fever, muscle rigidity, profuse sweating, respiratory problems, seizures, tachycardia, and loss of bladder control.
• Diabetic ketoacidosis: A dangerous build-up of acids in the blood.
• Pancreatitis: Inflammation of the pancreas.
• Pulmonary embolism: The formation of a blood clot in the lungs.
• Seizures
• Stroke
• Sudden cardiac death
• Suicide attempts

Elderly patients with dementia-related psychosis have a higher risk of death when taking antipsychotic drugs. Risperdal is not approved for this condition and should not be taken for this purpose.