Generic Name: promethazine (proe-METH-a-zeen)
Promethazine hydrochloride injection should not be used in pediatric patients less than 2 years old because of the potential for fatal respiratory depression. Respiratory depression, including fatalities, have been reported with use of promethazine in pediatric patients less than 2 years old in postmarketing experience. Exercise caution when administering promethazine hydrochloride injection to pediatric patients 2 years or older. Regardless of the administration route, promethazine hydrochloride injection can cause severe chemical irritation and damage to the tissue. Adverse reactions include burning, pain, thrombophlebitis, tissue necrosis, and gangrene, requiring surgical intervention, skin graft and/or amputation in some cases. Due to the risks of IV administration, the preferred route of administration is deep IM injection. Subcutaneous injection is contraindicated .
Medically reviewed by Drugs.com. Last updated on Oct 8, 2020.
Commonly used brand name(s)
In the U.S.
- Antinaus 50
Available Dosage Forms:
Therapeutic Class: Gastrointestinal Agent
Pharmacologic Class: Antihistamine
Chemical Class: Aliphatic
Uses for Promacot
Promethazine injection is used to relieve or prevent some types of allergy or allergic reactions. It works by preventing the effects of a substance called histamine, which is produced by the body. Histamine can cause itching, sneezing, runny nose, and watery eyes. It can sometimes close up the bronchial tubes (air passages of the lungs) and make breathing difficult.
Promethazine is also used to prevent and control motion sickness, nausea, vomiting, and dizziness. In addition, it may be used to help people go to sleep and control their pain or anxiety before or after surgery or other procedures.
Promethazine may also be used for other conditions as determined by your doctor.
This medicine is only available with your doctor's prescription.
Before using Promacot
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 this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine 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.
Appropriate studies have not been performed on the relationship of age to the effects of promethazine injection in the pediatric population. Use of promethazine injection is not recommended in children younger than 2 years of age because of the increased risk of respiratory depression. Caution should be used when this medicine is given to children 2 years of age and older.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of promethazine injection in the elderly. However, elderly patients may be more sensitive to the side effects of this medicine than in younger adults, and are more likely to have age-related heart or blood vessel disease or prostate problems, which may require an adjustment in the dose for patients receiving promethazine injection.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with 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 receiving this medicine, 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 this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
- Calcium Oxybate
- Magnesium Oxybate
- Potassium Oxybate
- Sodium Oxybate
Using this medicine 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.
- Aripiprazole Lauroxil
- Arsenic Trioxide
- Gabapentin Enacarbil
- Glycopyrronium Tosylate
- Inotuzumab Ozogamicin
- Morphine Sulfate Liposome
- Secretin Human
- Sodium Phosphate
- Sodium Phosphate, Dibasic
- Sodium Phosphate, Monobasic
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Aminolevulinic Acid
- Belladonna Alkaloids
- Betel Nut
- Evening Primrose
Interactions with food/tobacco/alcohol
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 this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Brain disease or injury or
- Breathing or lung problems (e.g., asthma, COPD) or
- Comatose state (unconscious) or
- Reye's syndrome or
- Sleep apnea, history of—Should not be used in patients with these conditions.
- Bladder-neck blockage or
- Bone marrow disease (e.g., agranulocytosis, leukopenia) or
- Enlarged prostate or
- Glaucoma, narrow-angle or
- Heart or blood vessel disease or
- Intestinal blockage or
- Liver disease (including jaundice) or
- Neuroleptic malignant syndrome, history of or
- Respiratory depression (very slow breathing) or
- Stomach ulcer or
- Urinary tract blockage or difficult urination—Use with caution. May make these conditions worse.
- Seizure disorders—This medicine may increase the chance of seizures especially in patients who are also using narcotic or anesthetic medicines.
Proper use of Promacot
This section provides information on the proper use of a number of products that contain promethazine. It may not be specific to Promacot. Please read with care.
A nurse or other trained health professional will give you this medicine. This medicine is given as a shot into a muscle or into a vein.
Your doctor will give you a few doses of this medicine until your condition improves, and then switch you to an oral medicine that works the same way. If you have any concerns about this, talk to your doctor.
Precautions while using Promacot
It is very important that your doctor check the progress of you or your child at regular visits to make sure this medicine is working properly. Blood tests may be needed to check for unwanted effects.
This medicine contains sodium metabisulfite. Make sure your doctor knows if you or your child have had an allergic reaction to sulfite in the past.
Check with your doctor right away if you or your child have burning, persistent or worsening pain at the injection site; or any involuntary muscle movements after receiving this medicine.
This medicine may affect blood sugar levels. If you or your child notice a change in the results of your blood or urine sugar tests or if you have any questions, check with your doctor.
This medicine will add to the effects of alcohol and other CNS depressants (medicines that make you drowsy or less alert). Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, antidepressants, or sleeping medicine; prescription pain medicine or narcotics; medicine for seizures or barbiturates; muscle relaxants; or anesthetics, including some dental anesthetics. Check with your medical doctor or dentist before taking any of the above while you or your child are taking this medicine.
Check with your doctor right away if you or your child have pale or blue lips, fingernails, or skin; difficult or troubled breathing; irregular, fast, slow, or shallow breathing; or shortness of breath. These could be signs of a condition called respiratory depression.
This medicine may cause some people to become dizzy, lightheaded, drowsy, or less alert than they are normally. Even if taken 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.
Promethazine can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. If you can, avoid people with infections. Check with your doctor immediately if you or your child think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
Check with your doctor right away if you or your child are having convulsions, difficulty in breathing, fast heartbeat, high fever, high or low blood pressure, increased sweating, loss of bladder control, severe muscle stiffness, unusually pale skin, or tiredness. These could be symptoms of a serious condition called neuroleptic malignant syndrome (NMS).
Check with your doctor right away if you or your child have pain or tenderness in the upper stomach; pale stools; dark urine; loss of appetite; nausea; unusual tiredness or weakness; or yellow eyes or skin. These could be symptoms of a liver problem.
Before you have any medical tests, tell the medical doctor in charge that you or your child are receiving this medicine. The results of some tests may be affected by this medicine.
This medicine 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.
This medicine may make your skin more sensitive to sunlight. Use a sunscreen when you are outdoors. Avoid sunlamps and tanning beds.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Promacot side effects
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.
Check with your doctor or nurse immediately if any of the following side effects occur:
- Convulsions (seizures)
- difficult or unusually fast breathing
- fast heartbeat or irregular pulse
- high fever
- high or low blood pressure
- increased sweating
- loss of bladder control
- severe muscle stiffness
- unusually pale skin
- unusual tiredness or weakness
Incidence not known
- Abdominal or stomach pain
- black, tarry stools
- blood in the urine
- bloody nose
- blurred vision
- chest pain or discomfort
- clay-colored stools
- cough or hoarseness
- dark urine
- decreased awareness or responsiveness
- difficulty with speaking
- double vision
- fast, pounding, or irregular heartbeat or pulse
- fever with or without chills
- fixed position of the eye
- heavier menstrual periods
- increases and decreases in blood pressure
- large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
- lightheadedness, dizziness, or fainting
- loss of appetite
- loss of balance control
- lower back or side pain
- mimicry of speech or movements
- muscle trembling, jerking, or stiffness
- noisy breathing
- painful or difficult urination
- peculiar postures or movements, mannerisms, or grimacing
- pinpoint red spots on the skin
- seeing double
- seeing, hearing, or feeling things that are not there
- severe sleepiness
- shortness of breath
- shuffling walk
- skin rash
- slow or irregular heartbeat
- sore throat
- sores, ulcers, or white spots on the lips or in the mouth
- stiffness of the limbs
- swollen glands
- tenderness, pain, swelling, warmth, skin discoloration, and prominent superficial veins over the affected area
- tightness in the chest
- twisting movements of the body
- uncontrolled movements, especially of the face, neck, and back
- unpleasant breath odor
- unusual bleeding or bruising
- vomiting of blood
- yellow eyes or skin
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptom of overdose
- Abnormal movements
- confusion as to time, place, or person
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- feeling of warmth
- holding false beliefs that cannot be changed by fact
- irregular, fast or slow, or shallow breathing
- pale or blue lips, fingernails, or skin
- pupils of the eyes, large and not moving or responding to light
- redness of the face, neck, arms, and occasionally, upper chest
- troubled breathing
- unusual excitement, nervousness, or restlessness
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:
Incidence not known
- Blistering, crusting, irritation, or reddening of the skin
- continuing ringing or buzzing or other unexplained noise in the ears
- discoloration of the skin
- dry mouth
- false or unusual sense of well-being
- hearing loss
- hives or welts
- increased sensitivity of the skin to sunlight
- lack of coordination
- loss of strength or energy
- muscle pain or weakness
- nasal stuffiness
- severe sunburn
- trouble sleeping
- unable to sleep
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.
Frequently asked questions
- Par promethazine with codeine vs Hi-Tech promethazine with codeine?
- How long does promethazine stay in your system?
More about promethazine
- Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Patient Tips
- Drug Images
- Drug Interactions
- Compare Alternatives
- Support Group
- Pricing & Coupons
- 291 Reviews
- Drug class: antihistamines
- FDA Alerts (3)
- Patient Information
- Promethazine injection
- Promethazine rectal
- Promethazine (Advanced Reading)
- Promethazine Injection, Intravenous (Advanced Reading)
- Promethazine Rectal (Advanced Reading)
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