Risperdal (Risperidone): Uses, Side Effects and Required Follow-Up

Risperdal (risperidone) is an atypical antipsychotic that doctors prescribe to treat schizophrenia and manic episodes of bipolar disorder. In children over 5 years old, it is sometimes used for irritability and aggressive behavior associated with autism, under specialist supervision. Its best-known effects are weight gain, drowsiness, hormonal disturbance (prolactin), and movement symptoms, so it requires regular follow-up. It should not be stopped suddenly, and it carries a special warning for older adults with dementia.

What is Risperdal and why is it prescribed?

Risperdal is the brand name of the active ingredient risperidone, which belongs to the class of atypical antipsychotics. It works by affecting chemicals in the brain such as dopamine and serotonin [2]. It does not cure the illness, but it reduces its symptoms, and it is available only with a prescription [2].

The medication comes as regular tablets, orally disintegrating tablets, and oral solution. Long-acting injections are also available and are given by healthcare professionals [2]. In the ClinicsJo directory, Risperdal appears as tablets at a strength of 2 mg. You can find more details on the Risperdal (Risperidone) page in the drug directory. The Jordan Food and Drug Administration (JFDA) regulates medicines and their listed prices in Jordan.

When is risperidone used? Schizophrenia, mania, and autism-related irritability

Documented uses include schizophrenia, manic symptoms of bipolar disorder, and aggressive or irritable behavior in children over 5 years old or adolescents with autism or conduct disorder [2]. MedlinePlus notes that the injection is used for schizophrenia and for type I bipolar disorder [1]. To learn more about the illness itself, you can read the article on schizophrenia and family follow-up or the guide to psychotic disorders, as well as the explanation of the difference between psychosis and schizophrenia.

Children with autism: a bridge, not an end goal

In children, the medication is used to calm severe episodes of irritability so that the child can benefit from behavioral training. The specialist determines the lowest effective dose and the shortest possible duration, with regular reviews of growth and weight, as the medication guide on the medication page explains. You can also search for child psychiatrists in Jordan.

How is Risperdal taken, and how long does it take to work?

Regular tablets are available in strengths from 0.25 mg to 6 mg. The dose chosen depends on the reason for use and on your response [3]. In schizophrenia in adults up to 65 years old, the dose usually starts low and is then increased. Most people feel improvement at daily doses between 4 and 6 mg [3]. These are the usual doses that the doctor determines, and they are not a reference for adjusting your dose yourself.

A doctor may reduce the dose and increase it very slowly for people who have kidney or liver problems [3]. For children, the dose is based on weight and is set by the doctor or as directed by the pharmacist, starting low and increasing gradually [3]. For this reason, a medication prescribed for one person should never be used by another, as explained in the answer about using a prescription medication prescribed for another family member.

Practical points for daily use

• The effect does not appear immediately. Some symptoms may take days, and sometimes months, to improve [2].
• Tablets and liquid can be taken with or without food. The liquid should be measured with the syringe or dropper provided, not with a kitchen spoon [3].
• Continue taking the medication even if you feel better, and do not stop it without consulting your doctor, who will reduce the dose gradually when needed [3].
• If you miss a once-daily dose, take it when you remember, unless less than 12 hours remain until the next dose. For twice-daily dosing, the limit is 8 hours. Do not double the dose. If you miss two or more doses, contact your doctor [3].
• Long-acting injections are given every two to eight weeks depending on the product, and the medication is usually tried by mouth before the first injection [1]. If you miss an injection appointment, contact your doctor to schedule a new one as soon as possible [1].

What are the common side effects of Risperdal?

Drowsiness, movement problems, and headache are common [2]. The UK NHS states that common side effects may affect up to 1 in 10 people. These include difficulty sleeping at night, headache, weight gain, changes in appetite, stomach pain, nausea, constipation, and diarrhea [4]. MedlinePlus adds dry mouth, increased saliva, tiredness, and dizziness [1]. Many of these symptoms ease as the body gets used to the medication. If disturbed sleep continues for more than a few weeks, tell your doctor [4].

What helps?

• Nausea: simple meals, and taking the medication after a light snack [4].
• Constipation: more fiber, enough water, and regular movement [4].
• Dizziness on standing: get up slowly, and sit with your feet on the floor for a few minutes before standing, especially after an injection [1].
• Drowsiness: do not drive or operate machinery until you know how the medication affects you, and avoid alcohol because it increases drowsiness [1].

To understand the difference between a side effect and a drug interaction, see this simple explanation.

Does Risperdal cause weight gain and high blood sugar? What follow-up is needed?

The medication may increase appetite, leading to weight gain [2]. Antipsychotics vary in this effect, but weight gain and increased appetite are expected with risperidone, as the drug guide shows. The NHS recommends a balanced diet without increasing meal sizes, avoiding high-calorie snacks, choosing fruit and vegetables when hungry, and exercising regularly [4].

Another risk is raised blood sugar, even in people who do not have diabetes. The risk of diabetes is already higher in people with schizophrenia and may increase with these medications [1]. Tell your doctor immediately if you develop severe thirst, frequent urination, severe hunger, blurred vision, or weakness, because high blood sugar can progress to life-threatening diabetic ketoacidosis if not treated early [1]. Signs of ketoacidosis include dry mouth, nausea, vomiting, shortness of breath, fruity-smelling breath, and decreased consciousness [1].

What should you do with your doctor?

• Tell them about a family history of diabetes, high cholesterol, heart disease, blood clots, and kidney or liver disease [1].
• Record your weight before starting, and then regularly, so you can compare it at each visit.
• Keep to the laboratory tests your doctor orders to check how your body responds to the medication [1]. Your doctor sets their timing and type.
• If the patient is a child, follow-up includes growth and weight at regular intervals.

Prolactin and movement symptoms: what should you watch for?

Hormonal effects (prolactin)

Risperidone raises the hormone prolactin in some patients. This may appear as breast enlargement, discharge or milk from the breast, a delayed or absent menstrual period, and reduced sex drive [1]. These are signs of a hormonal change [4]. Do not feel embarrassed to mention them to your doctor, as there are solutions. The doctor may change the medication if these symptoms persist for more than a few days [4]. Continue taking the medication in the meantime, and inform your doctor early without waiting for the next appointment. The drug guide advises caution in people with prolactin-secreting tumors.

Movement symptoms

At higher doses, restlessness, stiffness, or tremor may appear, and the doctor treats them by adjusting the dose. Involuntary movements of the face, tongue, or body that you cannot control, or muscle stiffness with difficulty moving, tremor, or drooling, are signs that require contacting your doctor immediately [4]. MedlinePlus also lists slowed movement, a shuffling walk, neck or throat muscle tightening, and difficulty swallowing [1]. Repeated falls should also be reported [1].

Is Risperdal safe for older adults with dementia?

This is the most important warning about this medication. The risk of death may increase in older adults with dementia who take antipsychotics, including risperidone, and the likelihood of stroke or transient stroke also increases [1]. MedlinePlus states that risperidone injections are not approved by the US Food and Drug Administration (FDA) for treating behavioral problems in older adults with dementia [1].

By contrast, the NHS mentions its use for a short period, which may be limited to a few weeks, for severe aggression in patients with Alzheimer's disease, at very low starting doses [2] [3]. Reconciling these two positions is a medical decision that weighs benefit against risk, and a family should not start it on its own. If you have a relative with dementia who takes this medication, ask the doctor why it is being used, how long it will continue, and when it will be reassessed. Parkinson's disease and dementia with Lewy bodies can also worsen with this medication, and caution is needed in people with a history of heart rhythm disorders (QT prolongation), according to the drug guide.

Drug interactions and precautions: pregnancy, alcohol, and other medications

Tell your doctor and pharmacist about all the medications, supplements, and herbs you take. MedlinePlus notes that cimetidine, ranitidine, and St. John's Wort may interact with risperidone [1]. The drug guide adds that fluoxetine and paroxetine raise its blood level, carbamazepine lowers it, blood pressure medications increase dizziness, and levodopa has a direct antagonistic effect. For more on antidepressants, see the patient guide to antidepressants.

• Pregnancy and breastfeeding: If you are pregnant, planning a pregnancy, or breastfeeding, tell your doctor, and do not stop the medication on your own. The medication may cause problems for the baby if taken in the last months of pregnancy [1].
• Heat: The body may have difficulty cooling down in extreme heat or warming up in extreme cold, so ask your doctor before strenuous physical activity [1].
• Alcohol: It is best to avoid it, especially in the first days [2].
• Medication list: Carry a written list of your medications to every visit [1].

When should you see a doctor, and when should you go to the emergency room?

See your doctor promptly if:

• Involuntary movements of the face, tongue, or body, stiffness, tremor, or drooling appear [4].
• Pain, swelling, and redness appear in the leg, as this may indicate a blood clot [4].
• Milky discharge, menstrual irregularity, or breast enlargement appears that bothers you or persists [1].
• Symptoms of high blood sugar appear (severe thirst, frequent urination, severe hunger, blurred vision) [1].
• Fever, cough, chills, or signs of infection appear [1].

Call 911 or go to the nearest emergency department if:

• High fever appears along with muscle stiffness, sweating, anxiety, or increased drooling. This may be neuroleptic malignant syndrome, which is rare and requires urgent treatment [4].
• Weakness appears on one side of the face or body, or difficulty speaking or thinking, loss of balance, or blurred vision. This may be a stroke [4].
• Chest pain with difficulty breathing, a racing heartbeat, or a seizure occurs [4].
• A painful erection lasts more than 3 to 4 hours (or more than one hour in people with sickle cell anemia) [4].
• Swelling of the lips, throat, or tongue, or difficulty swallowing or breathing occurs. These are signs of a severe allergic reaction. Read about drug allergy [4].
• The patient has taken more than the prescribed dose. This causes drowsiness, unusual movements, dizziness, a racing heart, and may lead to a seizure [3]. Do not drive yourself, and bring the medication box and your other medications with you [3].

How do you find the right psychiatrist to follow up on Risperdal treatment in Jordan?

The medication is usually prescribed and monitored by a psychiatrist, and for children, a child psychiatrist is preferred. Start with psychiatrists in Jordan, then choose your governorate, such as Amman, Irbid, or Zarqa. For your child, look for child psychiatry in Amman or in the governorate closest to you.

When reading a doctor's profile, check their specialty, clinic location, working hours, and the contact or booking methods available in the profile. ClinicsJo does not provide consultations or prescriptions through the website, and it does not evaluate the quality of doctors. It is a directory that makes it easier to reach them.

Useful questions for your appointment

1. Why did you choose this medication for my condition, and when should I expect improvement?
2. What is the expected duration of treatment, and when will we reassess the need for it?
3. What tests and measurements (weight, blood sugar, and others) will I need, and when?
4. Which symptoms (milk, menstrual changes, movements) require me to see you before the next appointment?
5. Do my current medications or supplements interact with it? What should I do if I miss a dose?
6. Do my plans for pregnancy or breastfeeding change the choice?

In summary, Risperdal is very beneficial when used at the lowest effective dose and under regular monitoring of weight, blood sugar, hormones, and movement. The information in this article is educational and does not replace your doctor's assessment of your condition.

Frequently asked questions

What is Risperdal and why is it prescribed?

Risperdal is the brand name of the active ingredient risperidone, which belongs to the class of atypical antipsychotics. Doctors prescribe it to treat schizophrenia and manic episodes of bipolar disorder. It works by affecting chemicals in the brain such as dopamine and serotonin. It does not cure the illness, but it reduces its symptoms, and it is available only with a prescription.

When is risperidone used?

Documented uses include schizophrenia, manic symptoms of bipolar disorder, and aggressive or irritable behavior in children over 5 years old or adolescents with autism or conduct disorder. In children, the medication is used to calm severe episodes of irritability so that the child can benefit from behavioral training. The specialist determines the lowest effective dose and the shortest possible duration.

How is Risperdal taken, and how long does it take to work?

The effect does not appear immediately. Some symptoms may take days, and sometimes months, to improve. Tablets and liquid can be taken with or without food, and the liquid should be measured with the syringe or dropper provided, not with a kitchen spoon. Continue taking the medication even if you feel better, and do not stop it without consulting your doctor.

What are the common side effects of Risperdal?

Drowsiness, movement problems, and headache are common. Common side effects also include difficulty sleeping at night, weight gain, changes in appetite, stomach pain, nausea, constipation, and diarrhea, as well as dry mouth, increased saliva, tiredness, and dizziness. Many of these symptoms ease as the body gets used to the medication. If disturbed sleep continues for more than a few weeks, tell your doctor.

Does Risperdal cause weight gain and high blood sugar?

The medication may increase appetite, leading to weight gain. Another risk is raised blood sugar, even in people who do not have diabetes, and the risk of diabetes is higher in people with schizophrenia. Tell your doctor immediately if you develop severe thirst, frequent urination, severe hunger, blurred vision, or weakness.

When should you see a doctor, and when should you go to the emergency room?

See your doctor promptly if involuntary movements, stiffness, tremor, or drooling appear. Call 911 or go to the nearest emergency department if high fever appears along with muscle stiffness, sweating, and anxiety, or if weakness appears on one side of the face or body or you have difficulty speaking.

Sources and references

1. Risperidone Injection: MedlinePlus Drug Information — MedlinePlus — U.S. National Library of Medicine. Accessed: 2026-10-26.
2. About risperidone — NHS (UK National Health Service). Accessed: 2026-10-26.
3. How and when to take risperidone — NHS (UK National Health Service). Accessed: 2026-10-26.
4. Side effects of risperidone — NHS (UK National Health Service). Accessed: 2026-10-26.