Specific Promethazine Warnings and Precautions
Some warnings and precautions to be aware of prior to taking promethazine
include the following:
- This medication should never be used in children under the age of two, as fatal breathing difficulties may occur. This can happen even if a proper dosage is calculated using the child's weight.
- Promethazine should not be given by IV push (when the medication is injected using a syringe directly into the IV line), due to the risk of tissue damage. Instead, it should be given by a slow IV drip or by an intramuscular injection. The medicine should never be injected into an artery or injected subcutaneously (just below the skin).
- If you are receiving promethazine through an IV, let your doctor know if you experience severe pain, as this may be a sign that the medication was administered incorrectly or is leaking from the vein into the surrounding tissue. This can cause permanent tissue damage, including gangrene. Seek immediate medical attention, and make sure your concerns are taken seriously.
- Nausea medications like promethazine should not be used to treat short-term vomiting or vomiting of unknown causes in children or adolescents. Promethazine should be used only for prolonged vomiting due to clearly established causes for this age group.
- Children with Reye's syndrome or liver disease should not take this medicine.
- Promethazine can cause drowsiness and may impair your mental and physical ability to drive, operate heavy machinery, or perform other similar tasks. Make sure you know how the drug affects you before driving or operating heavy machinery. Children should not ride bicycles, skateboard, or engage in other potentially hazardous activities while taking it.
- Promethazine can cause potentially fatal slow or irregular breathing. For this reason, people with COPD or sleep apnea should avoid this medication in most circumstances.
- This drug can increase the risk of seizures. This is especially important for individuals with a history of seizures or epilepsy.
- Promethazine can impair the ability of the bone marrow to produce blood cells. This may be especially problematic for people undergoing chemotherapy or radiation therapy.
- Promethazine can cause a life-threatening condition called neuroleptic malignant syndrome (NMS). Tell your healthcare provider right away if think you might have NMS. Some symptoms include:
- High fever
- Stiff muscles
- Irregular pulse or blood pressure
- Fast heart rate (tachycardia)
- Irregular heart rhythms (arrhythmias).
- Because of its anticholinergic effects, this medicine can cause glaucoma, Alzheimer's disease, or an enlarged prostate to become worse. Let your healthcare provider know if you experience worsening of any of these conditions while taking it.
- Promethazine can cause sensitivity to the sun. Avoid prolonged sun exposure during treatment.
- This medicine can cause odd, involuntary muscle movements. It can also cause strange, psychotic reactions, such as hallucinations. Let your healthcare provider know right away if such problems occur.
- Promethazine can interact with other medications (see Drug Interactions With Promethazine).
- Promethazine is considered a pregnancy Category C medication. This means that it might not be safe for use during pregnancy, although the full risks are not known. Talk to your healthcare provider about the risks and benefits of taking it when pregnant (see Phenergan and Pregnancy).
- It is unknown if promethazine passes through breast milk. Therefore, if you are breastfeeding or plan to start, discuss this with your healthcare provider prior to beginning treatment (see Phenergan and Breastfeeding).