Promethazine HCl

What is Promethazine HCl?

Promethazine hydrochloride (HCl), brand name: Phenergan, is an antihistamine that is used to treat the following:

  • Mild allergic skin reactions
  • “Hay fever” or a stuffy runny nose from allergy
  • Allergic reactions to blood or plasma
  • Watery, itchy eyes due to inhaled allergies and foods
  • Motion sickness
  • Serious allergic reactions along with epinephrine and other treatments
  • Dermographism (a form of hives known as “skin writing”)

Promethazine may also be used in the following circumstances:

  • Sedation, relief of anxiety, and production of light sleep from which the patient can be easily aroused
  • Sedation before or after surgery, or during child birth
  • Along with meperidine (Demerol) or other pain medications
  • Prevention and control of nausea and vomiting after surgery

Promethazine was approved by the U.S. Food and Drug Administration (FDA) in 1951.

FDA Alert on Promethazine

The FDA issued an alert in April 2006 to notify healthcare professionals and the public on the dangers of giving promethazine HCl in the form of tablets, syrups, suppositories or injectable to children under two years of age because the drug may cause breathing problems in these young children. Some of the breathing problems may be fatal. Parents and caregivers should be given advice by a healthcare professional before administering any form of promethazine HCl to children over two years old. Find out more what FDA has to say about this product here.

Who Should Not Use Promethazine?

Because of the risks and dangers, promethazine should not be given to the following:

  • Children under two years of age
  • Children who are vomiting, unless the vomiting is prolonged and there is a known cause
  • Patients with lung symptoms including asthma
  • Patients who are unconscious
  • Patients who are allergic to promethazine, any of the ingredients in promethazine, or to other phenothiazines

Health Risks of Promethazine

Serious breathing problems – those who have poor lung function should not use promethazine. This includes those who have breathing problems like sleep apnea or obstructive lung disease.

Severe drowsiness and reduced mental alertness – taking promethazine may cause drowsiness and would impair the person’s ability to operate machinery or drive a vehicle. It gets worse when taken with alcohol or other central nervous system (CNS) depressants such as pain medicines, sedatives, tranquilizers or other medicines for the treatment of depression.

Increased risk of seizures – those who have seizures or who take other medicines that increase the risk of seizures are advised to take caution and consult with a doctor before taking promethazine.

Neuroleptic malignant syndrome – those with neuroleptic malignant syndrome should not take promethazine. This syndrome is deadly and includes symptoms like fast heartbeat, fever, increased sweating, changes in pulse or blood pressure, irregular heart rhythm, mental changes and muscle rigidity.

Bone-marrow problems and blood cell production – patients with bone marrow problems or are taking medicines that affect the production of blood cells are advised against taking promethazine.

Side Effects of Promethazine

The following are the most common side effects of promethazine:

  • Breathing problems
  • Drowsiness
  • Changes in blood pressure
  • Blood cell changes
  • Skin reactions
  • Increased excitability or abnormal movements may occur after one dose of promethazine. If they do, consult your healthcare professional about using another medicine

What Should I Tell My Healthcare Professional?

Let your doctor know if you have the following before taking promethazine:

  • Breathing or lung problems
  • Seizures
  • Sleep apnea (breathing problems when sleeping)
  • Heart problems
  • Narrow-angle glaucoma
  • An enlarged prostate
  • Liver problems
  • A stomach ulcer
  • An intestinal blockage
  • A bladder blockage

Also let your doctor know if you:

  • Drink alcohol
  • Are trying to become pregnant, are already pregnant, or are breastfeeding

Are There Any Interactions With Drugs or Foods?

There are certain drugs that may interact with promethazine so let your doctor know any other medicines that you are taking, including prescription and non-prescription medications, herbal supplements, or vitamins and most especially:

  • Narcotics
  • Anti-anxiety medication
  • Sedatives
  • Sleeping pills
  • Antidepressants
  • Pain medicines
  • Tranquilizers
  • Epinephrine
  • Medicines called anticholinergics
  • A monoamine oxidase inhibitor (MAOI), which is used to treat depression or other mental disorders

Getting Legal Help

Even if most medicines are expected to have side effects, it is the duty of the manufacturer of these medicines to inform the medical community and the public of known risks associated with the drugs they produce. Failure to give adequate warning to the public and the medical community of the dangers of the drug makes the manufacturer liable for product liability for any injury that may be caused by their product.

If you or your loved one have suffered any of the dangerous symptoms or unusual reaction after taking promethazine, go to your doctor or the hospital as soon as possible. You may also consider consulting with an experienced attorney in order to get more information regarding your rights and possible remedies for the injuries you suffered because of the use of promethazine.

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