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.
Phenothiazines can sometimes cause serious unwanted effects. Tardive dyskinesia or tardive dystonia (muscle movement disorders) may occur and may not go away after you stop using the medicine. Signs of tardive dyskinesia or tardive dystonia include worm-like movements of the tongue, or other uncontrolled movements of the mouth, tongue, cheeks, jaw, body, arms, or legs. Another possible serious unwanted effect is the neuroleptic malignant syndrome (NMS). Signs and symptoms of NMS include severe muscle stiffness, fever, fast heartbeat, difficult breathing, increased sweating, and loss of bladder control. You and your doctor should discuss the good this medicine will do as well as the risks of taking it.
Stop taking this medicine and get emergency help immediately if any of the following effects occur:
Check with your doctor immediately if any of the following side effects occur:
Check with your doctor as soon as possible if any of the following side effects occur:
Phenothiazines may cause your urine to be dark. In most cases, this is not a sign of a serious problem. However, if your urine does become dark, discuss it with your doctor.
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:
After you stop using this medicine, your body may need time to adjust. The length of time this takes depends on the amount of medicine you were using and how long you used it. During this time, check with your doctor if you notice dizziness, nausea and vomiting, stomach pain, trembling of the fingers and hands, or any of the following signs of tardive dyskinesia or tardive dystonia:
Although not all of the side effects listed above have been reported for all of the phenothiazines, they have been reported for at least one of them. However, since all of the phenothiazines are very similar, any of the above side effects may occur with any of these medicines.
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.
Your doctor should check your progress at regular visits, especially during the first few months of treatment with this medicine. This will allow your dosage to be changed if necessary to meet your needs.
Do not stop taking this medicine without first checking with your doctor. Your doctor may want you to reduce gradually the amount you are taking before stopping completely. This is to prevent side effects and to keep your condition from becoming worse.
Do not take this medicine within 2 hours of taking antacids or medicine for diarrhea. Taking these products too close together may make this medicine less effective.
This medicine will add to the effects of alcohol and other central nervous system (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; barbiturates; medicine for seizures; muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above while you are using this medicine.
Before using any prescription or over-the-counter (OTC) medicine for colds or allergies, check with your doctor. These medicines may increase the chance of developing heatstroke or other unwanted effects, such as dizziness, dry mouth, blurred vision, and constipation, while you are taking a phenothiazine.
Before you have any medical tests, tell the medical doctor in charge that you are taking this medicine. The results of some tests (such as electrocardiogram [ECG or EKG] readings, the gonadorelin test, the metyrapone test, tests for phenylketonuria, and urine bilirubin tests) may be affected by this medicine.
Before having any kind of surgery, dental treatment, or emergency treatment, tell the medical doctor or dentist in charge that you are using this medicine. Taking phenothiazines together with medicines that are used during surgery, dental treatments, or emergency treatments may increase CNS depression or cause low blood pressure.
This medicine may cause some people to become drowsy or less alert than they are normally. Even if this medicine is taken only at bedtime, it may cause some people to feel drowsy or less alert on arising. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are not alert.
Phenothiazines may cause blurred vision, difficulty in reading, or other changes in vision, especially during the first few weeks of treatment. Do not drive, use machines, or do anything else that could be dangerous if you are not able to see well. If the problem continues or gets worse, check with your doctor.
Dizziness, lightheadedness, or fainting may occur, especially when you get up from a lying or sitting position. Getting up slowly may help. If the problem continues or gets worse, check with your doctor.
This medicine may make you sweat less, causing your body temperature to increase. Use extra care not to become overheated during exercise or hot weather while you are taking this medicine, since overheating may result in heatstroke. Also, hot baths or saunas may make you feel dizzy or faint while you are taking this medicine.
This medicine also may make you more sensitive to cold temperatures. Dress warmly during cold weather. Be careful during prolonged exposure to cold, such as in winter sports or swimming in cold water.
Phenothiazines may cause dryness of the mouth. For temporary relief, use sugarless candy or gum, 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.
Phenothiazines may cause your skin to be more sensitive to sunlight than it is normally. Exposure to sunlight, even for brief periods of time, may cause a skin rash, itching, redness or other discoloration of the skin, or a severe sunburn. When you begin taking this medicine:
Phenothiazines may cause your eyes to be more sensitive to sunlight than they are normally. Exposure to sunlight over a period of time (several months to years) may cause blurred vision, change in color vision, or difficulty in seeing at night. When you go out during the daylight hours, even on cloudy days, wear sunglasses that block ultraviolet (UV) light. Ordinary sunglasses may not protect your eyes. If you have any questions about the kind of sunglasses to wear, check with your medical doctor or eye doctor.
If you are taking a liquid form of this medicine, avoid getting it on your skin or clothing because it may cause a skin rash or other irritation.
If you are receiving this medicine by injection:
Tell your doctor if you have ever had any unusual or allergic reaction to medicines in this group 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.
Certain side effects, such as muscle spasms of the face, neck, and back, tic-like or twitching movements, inability to move the eyes, twisting of the body, or weakness of the arms and legs, are more likely to occur in children, especially those with severe illness or dehydration. Children are usually more sensitive than adults to the effects of phenothiazines.
Constipation, trouble urinating, dryness of mouth, confusion, problems with memory, dizziness or fainting, drowsiness, trembling of the hands and fingers, and problems with muscle movement, such as decreased or unusual movements, are especially likely to occur in elderly patients, who are usually more sensitive than younger adults to the effects of phenothiazines.
Although studies have not been done in pregnant women, some side effects, such as jaundice and movement disorders, have occurred in a few newborns whose mothers received phenothiazines during pregnancy. Studies in animals have shown that, when given to the mother during pregnancy, these medicines can decrease the number of successful pregnancies and cause problems with bone development in the offspring. Before taking this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.
Phenothiazines pass into breast milk and may cause drowsiness or unusual muscle movements in the nursing baby. It may be necessary for you to take a different medicine or to stop breast-feeding during treatment. Be sure you have discussed the risks and benefits of the medicine with your doctor.
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 any of these medicines, 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 medicines in this class with any of the following medicines is not recommended. Your doctor may decide not to treat you with a medication in this class or change some of the other medicines you take.
Using medicines in this class 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.
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. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other Medical Problems
The presence of other medical problems may affect the use of medicines in this class. Make sure you tell your doctor if you have any other medical problems, especially:
Phenothiazines are used to treat serious mental and emotional disorders, including schizophrenia and other psychotic disorders. Some are used also to control agitation in certain patients, severe nausea and vomiting, severe hiccups, and moderate to severe pain in some hospitalized patients. Chlorpromazine is used also in the treatment of certain types of porphyria, and with other medicines in the treatment of tetanus. Phenothiazines may also be used for other conditions as determined by your doctor.
Phenothiazines may cause unwanted, unattractive, and uncontrolled face or body movements that may not go away when you stop taking the medicine. They may also cause other serious unwanted effects. You and your doctor should talk about the good this medicine will do as well as the risks of using it. Also, your doctor should look for early signs of these effects at regular visits. Your doctor may be able to stop or decrease some unwanted effects, if they do occur, by changing your dose or by making other changes in your treatment.
These medicines are available only with your doctor’s prescription.
Levoprome(R) (methotrimeprazine) is no longer available in the United States. At the end of May 1998, Immunex Corporation stopped marketing it.
Once a medicine has been approved for marketing for a certain use, experience may show that it also is useful for other medical problems. Although these uses are not included in product labeling, phenothiazines are used in certain patients with the following medical conditions: