Risperidone

Mental health

Also known as Risperdal

Risperidone is an atypical antipsychotic. It dials down dopamine and serotonin signaling that has become overactive, which helps with hallucinations, racing or disorganized thoughts, mania, and severe irritability. It starts calming symptoms within days to weeks, though the full effect builds over time. Expect your doctor to keep an eye on your weight and blood sugar, and know that risperidone can raise a hormone called prolactin, which sometimes causes breast changes or missed periods — mention these if they happen.

How to take it

When

Once or twice a day, at the same times each day, exactly as prescribed.

Food

With or without food. The liquid form can be mixed with water, juice, or milk — but not cola or tea.

Avoid

Alcohol and other sedatives. Don't drive until you know how drowsy it makes you, and stand up slowly to avoid dizziness.

Boxed warning

Not for older adults with dementia-related psychosis — it raises the risk of death in that group. Never adjust or stop it on your own; talk to your prescriber first.

Missed a dose?

Take it as soon as you remember, unless it's nearly time for your next dose — in that case skip the missed one. Never take a double dose.

Common side effects

Drowsiness or feeling slowed down
Dizziness when standing up — rise slowly
Weight gain and increased appetite
Breast tenderness, discharge, or missed periods from raised prolactin — tell your doctor
Restlessness or mild shakiness

Call a doctor if

High fever with stiff muscles, confusion, and heavy sweating — this can be neuroleptic malignant syndrome, a rare emergency; call for help immediately
Repetitive movements you can't control, like lip smacking or tongue movements — possible tardive dyskinesia; call your doctor right away
Signs of very high blood sugar: extreme thirst, constant peeing, weakness, fruity-smelling breath — get medical help now
Fainting or a racing, irregular heartbeat — get help now
A painful erection lasting hours — this is an emergency, go to the ER

Educational only. This summary is drawn from public FDA labeling and MedlinePlus and simplified for readability. Your prescription label and your pharmacist always come first — doses and instructions vary from person to person.