Pimozide

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Generic Name: Pimozide Brand Name(s): Generics only. No brands available.

Uses

What is Pimozide used for?

Pimozide is used to reduce uncontrolled movements (motor tics) or outbursts of words/sounds (vocal tics) caused by Tourette’s syndrome. Pimozide is a medication that works by decreasing the activity of a natural substance (dopamine) in the brain.

Pimozide should not be used for mild symptoms. It should only be used if symptoms cause severe problems in everyday life and other medicines or treatments have not been effective.

How should I take Pimozide?

Take this medication by mouth with or without food, usually once a day at bedtime or as directed by your doctor.

Dosage is based on your medical condition and response to treatment. Your doctor may direct you to take a low dose at first, gradually increasing the dose to lower the chance of side effects such as shaking (tremors).

Do not take this drug more often or increase the dose. Your symptoms will not improve any faster, and the risk for heart rhythm problems will be increased. Follow your doctor’s directions carefully.

Your doctor may order an electrocardiogram (EKG) and laboratory tests before you start this medication. These tests are to find out whether you are at risk for heart rhythm problems from pimozide. Keep all medical/lab appointments.

Other drugs, such as stimulant medications (such as methylphenidate, dextroamphetamine), may occasionally worsen tics. Before deciding to start pimozide, your doctor may try to reduce your tics by lowering the stimulant dose. Consult your doctor for more details.

Avoid eating grapefruit or drinking grapefruit juice while using this medication unless your doctor instructs you otherwise. Grapefruit can increase the amount of this medication in your bloodstream. Consult your doctor or pharmacist for more details.

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.

Do not stop taking this medication without consulting your doctor. Your condition may become worse when the drug is suddenly stopped. Your dose may need to be gradually decreased.

Tell your doctor if your condition persists or worsens.

How do I store Pimozide?

Pimozide is best stored at room temperature away from direct light and moisture. To prevent drug damage, you should not store Pimozide in the bathroom or the freezer. There may be different brands of Pimozide that may have different storage needs. It is important to always check the product package for instructions on storage, or ask your pharmacist. For safety, you should keep all medicines away from children and pets.

You should not flush Pimozide down the toilet or pour them into a drain unless instructed to do so. It is important to properly discard this product when it is expired or no longer needed. Consult your pharmacist for more details about how to safely discard your product.

Precautions & warnings

What should I know before using Pimozide?

Before taking this medication, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: blood problems (such as a low white blood cell count), a certain eye condition (glaucoma), dementia, depression, heart problems (such as slow/fast/irregular heartbeat, low blood pressure), slow movement of the gut/intestines (such as chronic constipation, blockage), kidney disease, liver disease, brain disorder/tumor/injury, drug/alcohol/substance abuse, breast cancer, Parkinson’s disease, seizure disorder, a certain severe reaction to other antipsychotic-type medications (neuroleptic malignant syndrome-NMS), difficulty urinating (such as due to prostate problems).

This drug may make you dizzy or drowsy or cause vision changes. Alcohol or marijuana can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness or clear vision until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana.

Pimozide may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.

The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using pimozide, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death).

Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/”water pills”) or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using pimozide safely.

Before having surgery or imaging procedures (such as certain X-rays, CT scans) requiring the use of contrast dye (such as metrizamide), tell your doctor or dentist that you are using this medication and about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Older adults may be more sensitive to the side effects of this drug, especially drowsiness, dizziness, lightheadedness, and QT prolongation (see above). Drowsiness, dizziness, and lightheadedness can increase the risk of falling.

During pregnancy, this medication should be used only when clearly needed. Babies born to mothers who have used this drug during the last 3 months of pregnancy may rarely develop symptoms including muscle stiffness or shakiness, drowsiness, feeding/breathing difficulties, or constant crying. If you notice any of these symptoms in your newborn especially during their first month, tell the doctor right away.

Since untreated mental/mood problems (such as schizophrenia) can be a serious condition, do not stop taking this medication unless directed by your doctor. If you are planning pregnancy, become pregnant, or think you may be pregnant, immediately discuss with your doctor the benefits and risks of using this medication during pregnancy.

It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding.

Is it safe during pregnancy or breast-feeding?

There are no adequate studies in women for determining risk when using this Pimozide during pregnancy or while breastfeeding. Please always consult with your doctor to weigh the potential benefits and risks before taking Pimozide. Pimozide is pregnancy risk category C according to the US Food and Drug Administration (FDA).

FDA pregnancy risk category reference below:

  • A=No risk,
  • B=No risk in some studies,
  • C=There may be some risk,
  • D=Positive evidence of risk,
  • X=Contraindicated,
  • N=Unknown

Side effects

What side effects can occur from Pimozide?

Drowsiness, dizziness, lightheadedness, dry mouth, blurred vision, tiredness, or weakness may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

Dizziness and lightheadedness can increase the risk of falling. Get up slowly when rising from a sitting or lying position.

This drug may cause muscle/nervous system problems (extrapyramidal symptoms-EPS). Your doctor may prescribe another medication to decrease these side effects. Therefore, tell your doctor right away if you notice any of the following side effects: stiff muscles, severe muscle spasms/cramping (such as twisting neck, arching back, eyes rolling up), restlessness/constant need to move, shaking (tremor), slow/shuffling walk, drooling/trouble swallowing, mask-like expression of the face.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Some people using this medication do not have serious side effects.

This medication may cause a condition known as tardive dyskinesia. In some cases, this condition may be permanent. Tell your doctor right away if you develop any involuntary/repetitive muscle movements such as lip smacking/puckering, tongue thrusting, chewing, or finger/toe movements.

In rare cases, pimozide may increase your level of a certain chemical made by the body (prolactin). For females, this increase in prolactin may result in unwanted breast milk, missed/stopped periods, or difficulty becoming pregnant. For males, it may result in decreased sexual ability, inability to produce sperm, or enlarged breasts. If you develop any of these symptoms, tell your doctor right away.

Tell your doctor right away if any of these rare but very serious side effects occur: signs of infection (such as fever, persistent sore throat).

Seek immediate medical attention if any of these rare but very serious side effects occur: severe dizziness, fainting, slow heartbeat, seizures.

This medication may rarely cause a very serious condition called neuroleptic malignant syndrome (NMS). Get medical help right away if you have any of the following symptoms: fever, muscle stiffness/pain/tenderness/weakness, severe tiredness, severe confusion, sweating, fast/irregular heartbeat, dark urine, signs of kidney problems (such as change in the amount of urine).

A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

Not everyone experiences these side effects. There may be some side effects not listed above. If you have any concerns about a side-effect, please consult your doctor or pharmacist.

Interactions

What drugs may interact with Pimozide?

Some products that may interact with this drug include: anticholinergic/antispasmodic drugs (such as atropine, dicyclomine, scopolamine), drugs that increase the amount of dopamine in your body (such as bromocriptine, cabergoline, levodopa, pergolide, ropinirole).

Other medications can affect the removal of pimozide from your body, which may affect how pimozide works. Examples include aprepitant, azole antifungals (such as ketoconazole, itraconazole), delavirdine, HIV protease inhibitors (such as ritonavir, nelfinavir), hepatitis C virus protease inhibitors (such as boceprevir, telaprevir), macrolide antibiotics (such as azithromycin, erythromycin), nefazodone, SSRI antidepressants (such as fluvoxamine, paroxetine, sertraline), zileuton, among others.

Tell your doctor or pharmacist if you are taking other products that cause drowsiness including alcohol, marijuana, antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, and narcotic pain relievers (such as codeine).

Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.

Many drugs besides pimozide may affect the heart rhythm (QT prolongation). Examples include amiodarone, cisapride, citalopram/escitalopram, chlorpromazine, dofetilide, procainamide, quinidine, ranolazine, sotalol, macrolide antibiotics (such as clarithromycin, erythromycin), among others.

Pimozide may interact with other drugs that you are currently taking, which can change how your drug works or increase your risk for serious side effects. To avoid any potential drug interactions, you should keep a list of all the drugs you are using (including prescription drugs, nonprescription drugs and herbal products) and share it with your doctor and pharmacist. For your safety, do not start, stop, or change the dosage of any drugs without your doctor’s approval.

Does food or alcohol interact with Pimozide?

Pimozide may interact with food or alcohol by altering the way the drug works or increase the risk for serious side effects. Please discuss with your doctor or pharmacist any potential food or alcohol interactions before using this drug.

What health conditions may interact with Pimozide?

Pimozide may interact with your health condition. This interaction may worsen your health condition or alter the way the drug works. It is important to always let your doctor and pharmacist know all the health conditions you currently have.

Dosage

The information provided is not a substitute for any medical advice. You should ALWAYS consult with your doctor or pharmacist before using this Pimozide.

What is the dose of Pimozide for an adult?

Usual Adult Dose for Tourette’s Syndrome

Initial dose: 1 to 2 mg orally per day in divided doses

Maintenance dose: Typically less than 0.2 mg/kg or 10 mg/day, whichever is less

Maximum dose: 10 mg/day

Comments:

-Use should be limited to patients with Tourette’s Disorder whose development and/or daily life function is severely compromised by motor and phonic tics. This drug is not indicated for use as first-line therapy or in patients with tics that are merely annoying or cosmetically troublesome.

-Initial doses may be increased every other day if tolerated.

-Patients requiring doses greater than 4 mg/day should undergo CYP 450 2D6 genotyping.

Use: Suppression of motor and phonic tics in patients with Tourette’s Disorder who have failed to respond to standard treatment

Renal Dose Adjustments

Use with caution.

Liver Dose Adjustments

Use with caution

Dose Adjustments

CYP450 2D6 poor metabolizers:

Adults:

-Maximum dose: 4 mg orally per day

-Do not increase doses earlier than every 14 days

12 years and older:

-Maximum dose: 0.05 mg/kg/day

-Do not increase doses earlier than every 14 days

Neutropenia:

-Severe neutropenia (ANC less than 1000/mm3): Discontinue therapy.

QTc prolongation:

-Adults with increases over 0.52 seconds or 25% above baseline; children with increases over 0.47 seconds or 25% above baseline: Stop further dose increases and/or consider dose reductions.

Other Comments

Administration advice:

-Therapy should be initiated slowly and gradually.

General:

-A risk/benefit assessment is warranted for this drug, as use could result in serious adverse events (e.g., tardive dyskinesia, neuroleptic malignant syndrome, and sudden, unexpected death due to QT prolongation).

-When determining the initial dose for a patient, consideration should be given to the patient’s age, symptom severity, and previous response to other neuroleptic drugs. Patients should be on the lowest possible dose that suppresses symptoms but limits side effects.

-Patients should be evaluated regularly to verify that the lowest possible dose is used.

Monitoring:

-Complete Blood Count before and periodically during treatment

-ECGs at baseline and periodically during treatment

-Electrolyte levels periodically, especially in patients with electrolyte disturbances

Patient advice:

-Warn patients to avoid abrupt discontinuation of this drug.

-Tell patients to immediately report any signs/symptoms of neutropenia/leukopenia, neuroleptic malignant syndrome, or tardive dyskinesia.

-Patients should be advised to report all concurrent prescription and nonprescription medications or herbal products they are taking.

-Inform patients that this drug may cause drowsiness, and they should avoid driving or operating machinery until the full effects of the drug are known.

-Patients should be advised to speak to a healthcare provider if pregnant, intend to become pregnant, or are breastfeeding.

What is the dose of Pimozide for a child?

Usual Pediatric Dose for Tourette’s Syndrome

12 years and older:

-Initial dose: 0.05 mg/kg orally at bedtime

-Maximum dose: 0.2 mg/kg, not to exceed 10 mg/day

Comments:

-Use should be limited to patients with Tourette’s Disorder whose development and/or daily life function is severely compromised by motor and phonic tics. This drug is not indicated for use as first-line therapy or in patients with tics that are merely annoying or cosmetically troublesome.

-Doses may be increased every 3 days to a maximum of 0.2 mg/kg.

-CYP450 2D6 genotyping should be performed in patients taking greater than 0.05 mg/kg/day.

Use: Suppression of motor and phonic tics in patients with Tourette’s Disorder who have failed to respond to standard treatment

Precautions

Safety and efficacy have not been established in patients younger than 12 years.

How is Pimozide available?

Pimozide is available in the following dosage forms and strengths:

  • Oral tablet.

What should I do in case of an emergency or overdose?

In case of an emergency or an overdose, call your local emergency services or go to your nearest emergency room.

What should I do if I miss a dose?

If you miss a dose of Pimozide, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and take your regular dose as scheduled. Do not take a double dose.

Hello Health Group does not provide medical advice, diagnosis or treatment.

Sources

Review Date: April 11, 2018 | Last Modified: April 11, 2018

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