Phenothiazines (Systemic)

Before Using This Medicine

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 phenothiazines, the following should be considered:

Allergies - Tell your doctor if you have ever had any unusual or allergic reaction to phenothiazines. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes. Some of the phenothiazine dosage forms contain parabens, sulfites, or tartrazine.

Pregnancy - 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.

Breast-feeding - 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.

Children - 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.

Older adults - 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.

Other 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 phenothiazines, it is especially important that your health care professional know if you are taking any of the following:

• Amantadine (e.g., Symmetrel) or
• Antihypertensives (high blood pressure medicine) or
• Bromocriptine (e.g., Parlodel) or
• Deferoxamine (e.g., Desferal) or
• Diuretics (water pills) or
• Levobunolol (e.g., Betagan) or
• Medicine for heart disease or
• Metipranolol (e.g., OptiPranolol) or
• Nabilone (e.g., Cesamet) (with high doses) or
• Narcotic pain medicine or
• Pentamidine (e.g., Pentam) - Severe low blood pressure may occur

• Antidepressants (medicine for depression) - The risk of developing serious side effects, including severe constipation, low blood pressure, severe drowsiness, unusual body or facial movements, and changes in heart rhythm, may be increased

• Antipsychotics, other (medicine for mental illness) or
• Promethazine (e.g., Phenergan) or
• Trimeprazine (e.g., Temaril) - Severe low blood pressure or unusual body or facial movements may occur

• Antithyroid agents (medicine for overactive thyroid) - The risk of developing serious blood problems may be increased

• Astemizole (e.g., Hismanal) or
• Cisapride (e.g., Propulsid) or
• Disopyramide (e.g., Norpace) or
• Erythromycin (e.g., E.E.S., EryPed) or
• Probucol (e.g., Lorelco) or
• Procainamide (e.g., Procan SR) or
• Quinidine (e.g., Duraquin) - Serious changes in heart rhythm may occur

• Central nervous system (CNS) depressants (medicines that cause drowsiness) - Severe drowsiness and trouble in breathing may occur

• Epinephrine (e.g., Adrenalin) - Severe low blood pressure and fast heartbeat may occur

• Levodopa (e.g., Dopar) - Phenothiazines may prevent levodopa from working properly in the treatment of Parkinson's disease

• Lithium (e.g., Lithane, Lithizine, Lithobid) - Some unwanted effects, such as decreased or unusual body or facial movements, may be increased. The blood levels of the phenothiazine and/or lithium may be changed, so the medicines may not work properly. Your doctor may need to change your dose of either or both medicines

• Metoclopramide (e.g., Reglan) or
• Metyrosine (e.g., Demser) or
• Pemoline (e.g., Cylert) or
• Rauwolfia alkaloids (deserpidine [e.g., Harmonyl], rauwolfia serpentina [e.g., Raudixin], reserpine [e.g., Serpasil]) - Taking these medicines with phenothiazines may increase the chance of having decreased or unusual body or facial movements or may make the movement problems worse

• Pimozide (e.g., Orap) - Serious changes in heart rhythm, severe low blood pressure, or unusual body or facial movements may occur

Other medical problems - The presence of other medical problems may affect the use of phenothiazines. Make sure you tell your doctor if you have any other medical problems, especially:

• Alcohol abuse - Certain unwanted effects, such as heatstroke and liver disease, may be more likely to occur

• Blood disease or
• Breast cancer or
• Difficult urination or
• Glaucoma or
• Heart or blood vessel disease or
• Parkinson's disease or
• Seizure disorders, or history of or
• Stomach ulcers - Phenothiazines may make the condition worse

• Brain damage or
• Blood vessel disease in the brain - Serious increase in body temperature may occur

• Enlarged prostate - Difficulty in urinating may occur or may become more severe

• Liver disease - Phenothiazines may make the condition worse. Higher blood levels of phenothiazines may occur, increasing the chance of having unwanted effects

• Lung disease - Difficulty in breathing may become more severe. Decrease in cough reflex caused by phenothiazines may increase the risk of developing complications, such as pneumonia

• Pheochromocytoma or
• Kidney disease - Severe low blood pressure may occur

• Reye's syndrome - The risk that the phenothiazine will have unwanted effects on the liver may be increased