Generic Name: pimozide (PIM-oh-zide)
Medically reviewed by Drugs.com. Last updated on Sep 25, 2020.
Commonly used brand name(s)
In the U.S.
Available Dosage Forms:
Therapeutic Class: Antipsychotic
Pharmacologic Class: Dopamine Antagonist
Chemical Class: Diphenylbutylpiperidine
Uses for pimozide
Pimozide is used to treat symptoms of Tourette's syndrome. It is used only for patients with severe symptoms who cannot take or have not been helped by other medicines (e.g., haloperidol).
Pimozide works in the central nervous system to help control the vocal outbursts and uncontrolled, repeated movements of the body (tics) that may interfere with the patient's normal life. It will not completely cure the tics, but will help to reduce their number and severity.
Pimozide is available only with your doctor's prescription.
Before using pimozide
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For pimozide, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to pimozide or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of pimozide in children 12 years of age and older. However, safety and efficacy have not been established in children younger than 12 years of age.
No information is available on the relationship of age to the effects of pimozide in geriatric patients.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking pimozide, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using pimozide with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
- Aripiprazole Lauroxil
- Arsenic Trioxide
- Inotuzumab Ozogamicin
- Sodium Phosphate
- Sodium Phosphate, Dibasic
- Sodium Phosphate, Monobasic
Using pimozide with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Calcium Oxybate
- Gabapentin Enacarbil
- Glycopyrronium Tosylate
- Magnesium Oxybate
- Morphine Sulfate Liposome
- Potassium Oxybate
- Secretin Human
- Sodium Oxybate
Using pimozide with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Betel Nut
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using pimozide with any of the following is usually not recommended, but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use pimozide, or give you special instructions about the use of food, alcohol, or tobacco.
- Grapefruit Juice
Other medical problems
The presence of other medical problems may affect the use of pimozide. Make sure you tell your doctor if you have any other medical problems, especially:
- Blood or bone marrow problems (e.g., agranulocytosis) or
- Breast cancer, history of or
- Heart disease or
- Intestinal or bowel problems (e.g., blockage) or
- Leukopenia or neutropenia (low number of white blood cells) or
- Narrow angle glaucoma or
- Pituitary gland problems (e.g., tumors) or
- Seizures, history of or
- Urinary tract problems (e.g., blockage or difficult urination)—Use with caution. May make these conditions worse.
- Central nervous system depression or
- Heart rhythm problems (e.g., arrhythmia, congenital long QT syndrome), history of or
- Hypokalemia (low potassium in the blood) or
- Hypomagnesemia (low magnesium in the blood) or
- Tics other than those caused by Tourette's syndrome—Should not be used in patients with these conditions.
- Kidney disease or
- Liver disease—Higher blood levels of pimozide may occur, increasing the chance of side effects.
Proper use of pimozide
Take pimozide exactly as directed by your doctor to benefit your condition as much as possible. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered. To do so may increase the chance of side effects.
Do not eat grapefruit or drink grapefruit juice while you are taking pimozide. Grapefruit and grapefruit juice may change the amount of pimozide that is absorbed in the body.
It is best to take pimozide at bedtime.
The dose of pimozide will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of pimozide. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage form (tablets):
- For Tourette's syndrome:
- Adults—At first, 1 to 2 milligrams (mg) per day, taken in divided doses. Your doctor may increase your dose every other day as needed. However, the dose is usually not more than 10 mg per day.
- Children 12 years of age and older—Dose is based on body weight and must be determined by your doctor. The starting dose is usually 0.05 milligram (mg) per kilogram (kg) of body weight per day. Your doctor may increase your dose after 3 days as needed. However, the dose is usually not more than 10 mg per day.
- Children younger than 12 years of age—Use and dose must be determined by the doctor.
- For Tourette's syndrome:
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 go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Precautions while using pimozide
It is very important that your doctor should check the progress of you or your child at regular visits to make sure pimozide is working properly. Blood tests may be needed to check for unwanted effects. Your doctor may want also to check your heart rhythm while you are using pimozide.
You should not use pimozide if you or your child are using the following medicines: arsenic trioxide (Trisenox®), cisapride (Propulsid®), dolasetron mesylate (Anzemet®), droperidol (Dridol®, Inapsine®), levomethadyl acetate (Orlaam®), methylphenidate (Ritalin®), pemoline (Cylert®), pentamidine (Nebupent®), probucol, tacrolimus (Prograf®), zileuton (Zyflo®), amphetamines (such as Desoxyn®, Dexedrine®), medicine for heart rhythm problems (such as amiodarone, disopyramide, dofetilide, procainamide, quinidine, sotalol, Betapace®, Cardioquin®, Cordarone®, Norpace®, Procanbid®, Quinaglute®, or Tikosyn®), medicine for depression (such as amitriptyline, citalopram, escitalopram, fluoxetine, fluvoxamine, nefazodone, nortriptyline, paroxetine, sertraline, Celexa®, Elavil®, Lexapro™, Luvox®, Pamelor®, Paxil®, Prozac®, Sarafem®, Serzone®, Vivactil®, or Zoloft®), certain antibiotics (such as azithromycin, clarithromycin, dirithromycin, erythromycin, gatifloxacin, itraconazole, ketoconazole, levofloxacin, moxifloxacin, sparfloxacin, troleandomycin, Avelox®, Biaxin®, Ery-tab®, Levaquin®, Nizoral®, Sporanox®, Tao®, Tequin®, Zagam®, or Zithromax®), medicine to treat HIV infection (such as indinavir, nelfinavir, ritonavir, saquinavir, Crixivan®, Fortovase®, Invirase®, Norvir®, or Viracept®), medicine to treat malaria (such as halofantrine, mefloquine, Halfan®, or Lariam®), or medicine to treat mental illness (such as chlorpromazine, loxapine, mesoridazine, molindone, perphenazine, prochlorperazine, quetiapine, thioridazine, thiothixene, ziprasidone, Compazine®, Geodon®, Mellaril®, Serentil®, or Seroquel®). Using these medicines together with pimozide may increase risk for more serious side effects.
Pimozide can cause changes in heart rhythms, such as a condition called QT prolongation. It may change the way your heart beats and cause fainting or serious side effects in some patients. Contact your doctor right away if you or your child have any symptoms of heart rhythm problems, such as fast, pounding, or uneven heartbeats.
Pimozide may cause tardive dyskinesia (a movement disorder). Stop using pimozide and check with your doctor right away if you or your child have any of the following symptoms while taking pimozide: lip smacking or puckering, puffing of the cheeks, rapid or worm-like movements of the tongue, uncontrolled chewing movements, or uncontrolled movements of the arms and legs.
Check with your doctor right away if you or your child are having convulsions (seizures); difficulty with breathing; a fast heartbeat; high fever; high or low blood pressure; increased sweating; loss of bladder control; severe muscle stiffness; unusually pale skin; or tiredness. These could be symptoms of a serious condition called neuroleptic malignant syndrome (NMS).
Stop using pimozide and check with your doctor if you notice any signs of fever, chills, or sore throat. These could be symptoms of an infection resulting from low white blood cell counts.
Do not suddenly stop taking pimozide without first checking with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping completely. This will allow your body time to adjust and help to avoid worsening of your medical condition.
Pimozide will add to the effects of alcohol and other CNS depressants (medicines that slow down the nervous system, possibly causing drowsiness). Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; medicine for seizures or barbiturates; muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above while you or your child are using pimozide.
Pimozide may cause some people to become dizzy, drowsy, or less alert or to have blurred vision or muscle stiffness, especially as the amount of medicine is increased. Even if you take pimozide at bedtime, you may feel drowsy or less alert on arising. Make sure you know how you react to pimozide before you drive, use machines, or do anything else that could be dangerous if you are not alert, not able to see well, or if you do not have good muscle control.
Although not a problem for many patients, dizziness, lightheadedness, or fainting may occur when you get up from a sitting or lying position. Getting up slowly may help. If the problem continues or gets worse, check with your doctor.
Before having any kind of surgery, dental treatment, or emergency treatment, tell the medical doctor or dentist in charge that you are using pimozide. Taking pimozide together with medicines that are used during surgery or dental or emergency treatment may increase the CNS depressant effects.
Pimozide may cause dryness of the mouth. For temporary relief, use sugarless gum or candy, melt bits of ice in your mouth, or use a saliva substitute. However, if your mouth continues to feel dry for more than 2 weeks, check with your medical doctor or dentist. Continuing dryness of the mouth may increase the chance of dental disease, including tooth decay, gum disease, and fungus infections.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Pimozide side effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
- Difficulty with speaking
- dizziness or fainting
- fast or irregular heartbeat
- lack of facial expression
- loss of balance control
- mood or behavior changes
- restlessness or need to keep moving
- shuffling walk
- slowed movements
- stiffness of the arms and legs
- swelling or soreness of the breasts (less common in males)
- trembling and shaking of the fingers and hands
- unusual secretion of milk (rare in males)
Less common or rare
- Difficulty with swallowing
- inability to move the eyes
- increased blinking or spasms of the eyelid
- lip smacking or puckering
- menstrual changes
- muscle spasms, especially of the face, neck, or back
- puffing of the cheeks
- rapid or worm-like movements of the tongue
- skin rash and itching
- sore throat and fever
- swelling of the face
- uncontrolled chewing movements
- uncontrolled movements of the neck, trunk, arms, or legs, including twisting movements
- unusual bleeding or bruising
- unusual facial expressions or body positions
- yellow eyes or skin
- Convulsions (seizures)
- difficult or unusually fast breathing
- fast heartbeat or irregular pulse
- fever (high)
- high or low (irregular) blood pressure
- increased sweating
- loss of bladder control
- muscle stiffness (severe)
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
- dizziness (severe)
- muscle trembling, jerking, or stiffness (severe)
- troubled breathing (severe)
- uncontrolled movements (severe)
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
- Blurred vision or other vision problems
- dizziness, lightheadedness, or fainting when getting up from a lying or sitting position
- dryness of the mouth
- skin discoloration
- Decreased sexual ability
- loss of appetite and weight
- mental depression
- nausea and vomiting
- tiredness or weakness
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
More about pimozide
- Side Effects
- During Pregnancy or Breastfeeding
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- 21 Reviews
- Drug class: miscellaneous antipsychotic agents
- FDA Alerts (2)
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