Along with their needed effects, thioxanthenes can sometimes cause serious side effects. Tardive dyskinesia (a movement disorder) may occur and may not go away after you stop using the medicine. Signs of tardive dyskinesia include fine, worm-like movements of the tongue, or other uncontrolled movements of the mouth, tongue, cheeks, jaw, or arms and legs. Other serious but rare side effects may also occur. Some of these side effects, including severe muscle stiffness, fever, unusual tiredness or weakness, fast heartbeat, difficult breathing, increased sweating, loss of bladder control, and seizures, may be the sign of a condition called neuroleptic malignant syndrome. You and your doctor should discuss the good this medicine will do as well as the risks of taking it.
Although not all of these side effects may occur, if they do occur they may need medical attention.
Stop taking this medicine and get emergency help immediately if any of the following effects occur:
Check with your doctor as soon as possible if any of the following side effects occur:
Symptoms of overdose
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 taking this medicine your body may need time to adjust, especially if you took this medicine in high doses or for a long time. If you stop taking it too quickly, the following withdrawal effects may occur and should be reported to your doctor:
Although not all of the side effects listed above have been reported for all thioxanthenes, they have been reported for at least one of them. However, since these medicines are very similar, any of the above side effects may occur with any of them.
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. This will allow the dosage of the medicine to be adjusted when necessary and also will reduce the possibility of side effects.
Do not stop taking this medicine without first checking with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping completely. This is to prevent side effects and to prevent your condition from becoming worse.
This medicine 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; barbiturates; medicine for seizures; muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any such depressants while you are using this medicine.
Do not take this medicine within an hour of taking antacids or medicine for diarrhea. Taking them too close together may make this medicine less effective.
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 thioxanthenes together with medicines that are used during surgery or dental or emergency treatments may increase the CNS depressant effects.
This medicine may cause some people to become drowsy or less alert than they are normally, especially during the first few weeks the medicine is being taken. Even if you take this medicine only at bedtime, you may 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.
Dizziness, lightheadedness, or fainting may occur while you are taking this medicine, 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 heat stroke. Also, hot baths or saunas may make you feel dizzy or faint while you are taking this medicine.
Thioxanthenes 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:
If you have a severe reaction from the sun, check with your doctor.
This medicine 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.
If you are taking a liquid form of this medicine, try to avoid spilling it on your skin or clothing. Skin rash and irritation have been caused by similar medicines.
If you are receiving this medicine by injection:
This medicine may be taken with food or a full glass (8 ounces) of water or milk to reduce stomach irritation.
For patients taking thiothixene oral solution:
Do not take more of this medicine or take it more often than your doctor ordered. This is particularly important when this medicine is given to children, since they may react very strongly to its effects.
Sometimes this medicine must be taken for several weeks before its full effect is reached.
The dose medicines in this class 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 these medicines. 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.
If you miss a dose of this medicine, 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.
Keep out of the reach of children.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Do not keep outdated medicine or medicine no longer needed.
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, who are usually more sensitive than adults to the side effects of thioxanthenes.
Constipation, dizziness or fainting, drowsiness, dryness of mouth, trembling of the hands and fingers, and symptoms of tardive dyskinesia (such as rapid, worm-like movements of the tongue or any other uncontrolled movements of the mouth, tongue, or jaw, and/or arms and legs) are especially likely to occur in elderly patients, who are usually more sensitive than younger adults to the effects of thioxanthenes.
Studies have not been done in pregnant women. Although animal studies have not shown that thioxanthenes cause birth defects, the studies have shown that these medicines cause a decrease in fertility and fewer successful pregnancies.
It is not known if thioxanthenes pass into the breast milk. However, similar medicines for nervous, mental, or emotional conditions do pass into breast milk and may cause drowsiness and increase the risk of other problems in the nursing baby. Be sure you have discussed the risks and benefits of this 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:
The family of medicines known as thioxanthenes are used in the treatment of nervous, mental, and emotional conditions. Improvement in such conditions is thought to result from the effect of these medicines on nerve pathways in specific areas of the brain.
Thioxanthene medicines are available only with your doctor’s prescription.