Promethazine (Injection, Intravenous)

Promethazine can be used to prevent some types of allergic reactions and can also be used to control motion sickness and to help people sleep following surgery.


Promethazine is used to prevent or relieve certain allergies and certain forms of allergic reaction. The treatment is an antihistamine that works to prevent the effects of histamine in the body. This naturally produced substance causes itching, sneezing, running eyes and running nose. In severe cases it can also make it difficult to breath because it blocks up the air passages within the lungs.

Promethazine can also be used for the treatment of some other conditions. It can be used to control and sometimes prevent the effects of motion sickness, nausea, dizziness and vomiting. This treatment can also be used to help people to sleep before or after they undergo surgery and other medical procedures.

Your doctor may also prescribe Promethazine for the treatment of other conditions and this will be determined by your doctor.

This medication is injected into the patient and is available only when prescribed by a doctor.

Condition treated

  • Motion sickness
  • Allergic reactions
  • Nausea
  • Dizziness

Type Of Medicine

  • Antihistamine

Side Effects

In addition to the desired effects occurring from the use of Promethazine, other side effects that are unwanted may also occur. In some cases these side effects may require that the patient seek urgent medical attention. In other cases, however, side effects may be mild and do not necessitate seeking medical attention.

Patients experiencing the following side effects from the use of Promethazine should contact their doctor or nurse immediately:

Occurring only rarely:

  • Changed blood pressure
  • Convulsions or seizures
  • Difficulty with breathing
  • High fever
  • Increased heartbeat
  • Increased sweating when cool
  • Irregularity of pulse
  • Loss of control of bladder
  • Severe muscle stiffness
  • Unusual paleness of the skin
  • Unusual tiredness
  • Unusual weakness
  • Unusually fast breathing

Frequency of incidence not known:

  • Abdominal pains
  • Blood appearing in the urine
  • Bloodiness of the nose
  • Blurring of the vision
  • Changes in blood pressure
  • Chest pains or discomfort across the chest
  • Chills when warm
  • Coughing
  • Darkened urine
  • Decreased awareness of surrounding
  • Decreased responsiveness
  • Difficulty with speaking and communication
  • Dizziness
  • Double vision
  • Drooling
  • Fainting or faintness
  • Fever occurring with or without chills
  • Headaches
  • Hive-like swelling that may occur on the:
    • Tongue
    • Throat
    • Sex organs
    • Lips
    • Legs
    • Hands
    • feet
    • Face
    • Eyelids
  • Hoarseness
  • Inability to move the eye
  • Increased menstrual period flow
  • Increased prominence of superficial veins
  • Involuntary mimicry of speech or movements
  • Involuntary twisting movements of the body
  • Irregular heartbeat and/or pulse
  • Itchiness
  • Lack of appetite
  • Lightheadedness
  • Loss of balance control
  • Lower back pains
  • Muscle jerking
  • Muscle stiffness
  • Muscle trembling
  • Mutism
  • Nausea
  • Negativism
  • Pain or difficulty experienced during urination
  • Red spots appearing on the skin
  • Restlessness
  • Seeing, hearing, or feeling things that are not experienced by others
  • Severe sleepiness
  • Shortness of breath without exertion
  • Shuffling when walking
  • Side pain
  • Skin rash
  • Slowing or irregularity of the heartbeat
  • Soreness of the throat
  • Sores or ulcers in the mouth
  • Stiffening of the limbs
  • Stomach pains
  • Stools with a clay-like coloration
  • Swelling of the glands
  • Tarry stools with a black appearance
  • Tenderness, pain, swelling, warmth, skin discoloration at injection site
  • Tightness across the chest
  • Tremors
  • Uncontrolled movements of the face, neck, back or other body parts
  • Unpleasant breath odor
  • Unusual bleeding
  • Unusual bruising
  • Unusually audible breathing
  • Unusually postures, movements, mannerisms or grimaces
  • Vomiting of blood
  • Wheezing
  • White spots on the lips or mouth
  • Yellowing of the eyes
  • Yellowing of the skin

Other side effects may also occur that would not normally require that you seek medical attention. Over time these side effects may abate and they are not normally a sign of wider medical problems. Inform your doctor if these side effects are ongoing or bothersome:

  • Blistering of the skin
  • Continued ringing or unexplained noise not heard by others
  • Crusting or irritation of the skin
  • Discoloration of the skin
  • Drowsiness
  • Dryness of the mouth
  • Excitation
  • False or unusual sense of well-being
  • Hives
  • Inability to sleep
  • Increased sensitivity of the skin to sunlight
  • Lack of or loss of coordination
  • Loss of hearing
  • Lost strength or energy
  • Muscle pain
  • Muscle weakness
  • Nasal stuffiness
  • Nervousness
  • Reddening of the skin
  • Severe sunburn
  • Sleeplessness
  • Troubled sleeping
  • Vomiting
  • Welts

It is also possible to overdose on this treatment with life-threatening consequences. If you believe that you or someone else has taken too great a dose of this treatment then you should contact the emergency services immediately. Symptoms of overdose include the following:

  • Abnormal movements
  • Confusion about the time, year, place or identity
  • Dizziness, faintness or lightheadedness when rising from lying or sitting down
  • Unusual feeling of warmth
  • The holding false beliefs that cannot be changed when presented with fact
  • Hyperexcitability
  • Irregularity of breathing
  • Nightmares
  • Paling or blueness of lips, fingernails or skin
  • Increased size of pupils and reduction of their reaction to light
  • Reddening of the face, neck, arms or the upper chest
  • Sweating
  • Trouble with breathing
  • Unusual excitement, nervousness or restlessness

Other side effects can also occur that have not been listed here. If you experience other side effects then you should contact your physician for advice as soon as possible. If you are concerned about your immediate health, however, then you should always contact the emergency services.


This medication is injected directly into the vein or muscle and should be administered by a nurse or other trained medical professional.

This treatment will be given to you by injection until your condition improves and you have become stable. Once you have stabilized you will be given an oral treatment that works in the same manner to take.

The dose given will be determined by the doctor. The following information is for guidance only and doses should not be changed based on the following:

For the treatment of allergic reactions:

  • Usual adult dose is 25mg. This can be repeated after 2 hours if required.

For sedation of the patient:

  • Usual adult dose is 25-50mg.

For control of vomiting and nausea:

  • Adults 12.5-25mg taken not more frequently than once every 4 hours.

For preoperative and postoperative use:

  • Adults 25-50mg. Use can be combined with other medications where required.

If you are prescribed an oral dose following treatment then you must follow dosing instructions for the oral prescription of this medication.


Promethazine can interact with a wide range of treatments in the body. In some cases medication may react violently with severe consequences for the health of the patient. In other cases different medications may prevent other treatments from working or may increase the severity of unwanted side effects. You should inform your doctor of all treatments that you are receiving before you begin treatment with this medication. This is especially important in the following cases:

The use of Promethazine with the following medication is not recommended. Your doctor may need to change one or more of your prescriptions if you are taking any of the following:

  • Ziprasidone
  • Thioridazine
  • Terfenadine
  • Sparfloxacin
  • Sodium Oxybate
  • Saquinavir
  • Piperaquine
  • Pimozide
  • Metoclopramide
  • Mesoridazine
  • Dronedarone
  • Cisapride
  • Bromopride
  • Bepridil
  • Amisulpride
  • Amifampridine

The use of Promethazine with the following medications would not normally be recommended. In some cases treatment with both medications may be required and they may be prescribed together. Your doctor may change the dose or the frequency of use in these cases:

  • Zuclopenthixol
  • Zolpidem
  • Voriconazole
  • Vinflunine
  • Vemurafenib
  • Vardenafil
  • Vandetanib
  • Triptorelin
  • Trimipramine
  • Trifluoperazine
  • Tramadol
  • Toremifene
  • Tiotropium
  • Tetrabenazine
  • Telithromycin
  • Telavancin
  • Tapentadol
  • Tacrolimus
  • Sunitinib
  • Sulpiride
  • Sufentanil
  • Sotalol
  • Sorafenib
  • Solifenacin
  • Sodium Phosphate, Monobasic
  • Sodium Phosphate, Dibasic
  • Sodium Phosphate
  • Sevoflurane
  • Salmeterol
  • Remifentanil
  • Ranolazine
  • Quinine
  • Quetiapine
  • Protriptyline
  • Propafenone
  • Prochlorperazine
  • Procarbazine
  • Procainamide
  • Posaconazole
  • Pitolisant
  • Pimavanserin
  • Periciazine
  • Perflutren Lipid Microsphere
  • Pentazocine
  • Pentamidine
  • Pazopanib
  • Pasireotide
  • Panobinostat
  • Paliperidone
  • Oxymorphone
  • Oxycodone
  • Ondansetron
  • Ofloxacin
  • Octreotide
  • Nortriptyline
  • Norfloxacin
  • Nilotinib
  • Nafarelin
  • Moxifloxacin
  • Morphine Sulfate Liposome
  • Morphine
  • Mifepristone
  • Metronidazole
  • Metrizamide
  • Methadone
  • Mefloquine
  • Meclizine
  • Lumefantrine
  • Lopinavir
  • Lithium
  • Levorphanol
  • Levofloxacin
  • Leuprolide
  • Lapatinib
  • Ketoconazole
  • Ivabradine
  • Isradipine
  • Imipramine
  • Iloperidone
  • Ibutilide
  • Hydroxyzine
  • Hydroxychloroquine
  • Hydromorphone
  • Hydrocodone
  • Histrelin
  • Haloperidol
  • Halofantrine
  • Granisetron
  • Goserelin
  • Gonadorelin
  • Gemifloxacin
  • Gatifloxacin
  • Fluoxetine
  • Fluconazole
  • Flibanserin
  • Flecainide
  • Fingolimod
  • Fentanyl
  • Escitalopram
  • Erythromycin
  • Efavirenz
  • Droperidol
  • Doxylamine
  • Donepezil
  • Domperidone
  • Dolasetron
  • Dofetilide
  • Disopyramide
  • Dihydrocodeine
  • Deslorelin
  • Desipramine
  • Delamanid
  • Degarelix
  • Dasatinib
  • Dabrafenib
  • Crizotinib
  • Codeine
  • Clozapine
  • Clomipramine
  • Clarithromycin
  • Citalopram
  • Ciprofloxacin
  • Chlorpromazine
  • Chloroquine
  • Carbinoxamine
  • Butorphanol
  • Buserelin
  • Bupropion
  • Buprenorphine
  • Bromopride
  • Bromazepam
  • Azithromycin
  • Astemizole
  • Asenapine
  • Arsenic Trioxide
  • Aripiprazole
  • Apomorphine
  • Anagrelide
  • Amoxapine
  • Amitriptyline
  • Amiodarone
  • Alfuzosin

Promethazine when used in conjunction with the following medications can increase the risk of certain side effects occurring. Your doctor may change the dose or frequency of use of one or more of the following treatments:

  • Phenylalanine
  • Midodrine
  • Meperidine
  • Evening Primrose
  • Betel Nut
  • Belladonna Alkaloids
  • Belladonna

Interactions with other medications may also occur so it is important that you inform your doctor of all treatments that you are taking before use of this treatment. The medications listed herein have been chosen for severity and the list is not all-inclusive.

Other medical conditions from which you suffer can also impact the use of this treatment. You should inform your doctor of all medical conditions from which you suffer. This is especially important in the following cases:

Promethazine should not be used in patients with the following conditions:

  • Brain injury
  • Brain disease
  • Comatose state
  • Raye's syndrome
  • History of sleep apnea

The following conditions may be worsened by the use of Promethazine:

  • Blockage of the bladder-neck
  • Bone marrow disease
  • Enlargement of the prostate
  • Narrow angle-glaucoma
  • Heart disease
  • Blood vessel disease
  • Intestinal blockage
  • Liver disease
  • Neuroleptic malignant syndrome
  • Respiratory depression
  • Ulceration of the stomach
  • Blockage of the urinary tract
  • Seizure disorders

Other medical conditions not listed herein may also affect the use of this treatment. Ensure you share your full medical history before beginning treatment.


Before using this treatment it is important that you understand the risks of use and weigh these against the benefits of use. This decision will be made by you and your doctor and you should ensure that you have considered the following:

Allergies: Inform your doctor of all allergies from which you suffer. This is particularly important if you have ever had an unusual reaction to any other medications as this may prohibit use.

Pediatric: Injection would not be recommended in children under the age of 2. Below this age there is an increased risk of the development of respiratory depression. Caution should always be exercised when the treatment is being used on young children.

Geriatric: Treatment has been shown to be safe and effective in elderly patients. Elderly patients will, however, be more likely to suffer from other medical conditions that may limit use. Extra caution should be exercised in these patients.

Pregnancy: Use during pregnancy should be carried out with caution. Risks from use do exist but treatment with this medication may still be the best treatment available. You should inform your doctor before treatment if you are pregnant.

Breastfeeding: Risks from breastfeeding during treatment are unknown. Patients should inform their doctor before treatment if they are nursing an infant.

During the use of this treatment the doctor will need to make regular checks on the patient. Blood tests may be required in order to determine the presence of unwanted side effects.

Allergies to sulfates can prohibit the use of this treatment. Ensure that your doctor is aware of any sulfate allergies that you have suffered from in the past.

You should inform the doctor immediately if burning sensations occur at the injection site prior to use. Any involuntary muscle movements should be reported straight away too.

Use of this treatment can effect the level of sugar in the blood. This can cause problems in diabetic patients and you should prepare for this by discussing it with your doctor before receiving the treatment.

This medication will intensify the effects of certain treatments and substances that affect the central nervous system. These substances include CNS depressants such as:

  • Antihistamines
  • Treatments for colds
  • Sedatives
  • Pain medications
  • Narcotics
  • Seizure treatments
  • Antidepressants
  • Sleeping medications
  • Relaxants
  • Anesthetics
  • Alcohol

These should be avoided during treatment and you should inform your doctor before use.

Respiratory depression may occur from the use of this treatment, particularly in younger patients. You should contact your doctor immediately if any of the following symptoms of respiratory depression occur:

  • Paleness or blueness of the fingernails, lips or skin.
  • Difficulty in breathing
  • Shortness of breath

This treatment can make some patients dizzy or drowsy. You should ensure that you are fully aware, alert and safe before driving or operating machinery. You should not do anything that would put you or others at risk after taking this treatment until you know you are safe to do so. Remember that it is your legal responsibility to ensure that you are safe to carry out such tasks.

Promethazine will temporarily lower the count of white blood cells in your body. This will in turn increase the risk of you developing an infection. To counteract this risk you should avoid contact with those suffering from an infection and should report any suspected infections to your doctor for treatment promptly. You should also exercise an increased level of hygiene when taking this treatment to avoid infection.

Neuroleptic malignant syndrome can develop in patients during use of this treatment. You should consult your doctor immediately if any of the symptoms of this occur. These include the following:

  • Convulsions
  • Difficulty breathing
  • Increased heartrate
  • Increased sweating
  • High fever
  • Changed blood pressure
  • Loss of control of the bladder
  • Unusual paleness of the skin
  • Tiredness

Liver problems can occur during use of Promethazine. You should contact your doctor immediately if you experience any of the following symptoms of a developing liver problem:

  • Paleness of stools
  • Darkened urine
  • Lost appetite
  • Nausea
  • Unusual tiredness
  • Unusual weakness
  • Yellowing of the eyes
  • Yellowing of the skin

Before undergoing any medical tests you should inform the medical professional that you are taking Promethazine. This treatment can affect results and lead to misdiagnosis.

This medication can cause a dryness of the mouth. Sucking bits of ice or chewing sugarless gum can help to alleviate this side effect. If the side effect is ongoing, however, then you should report this to your doctor. Prolonged dryness of the mouth can cause gum disease, tooth decay and other oral problems to occur.

You should use suncream when in direct sunlight when undergoing treatment with Promethazine. This treatment will expose you to a greater sensitivity to light that will make you burn more easily even in low levels of light.

You should not take any other medications in conjunction with this treatment unless you are directed to by your doctor.


This medication should be stored at room temperature away from moisture, heat and direct sunlight.

Medications should always be stored out of the reach of children.

This medication should be disposed of properly and should not be flushed down the toilet or poured down the drain.


Promethazine is an antihistamine treatment that is used to control or prevent symptoms of allergic reactions, motion sickness, nausea and sickness. It can also be used to help patients sleep and can be used to calm the patient before and after treatment for improved healing and results.

Promethazine is an injected treatment that is administered by a nurse or trained professional. It is injected either into the muscle or into the vein. Patients treated with injected Promethazine may then be prescribed an additional oral dose of Promethazine to use afterwards. This treatment works in the same way and can extend the effects of the treatment.

Promethazine can cause some serious side effects in certain patients and can expose the patient to the risk of developing other medical conditions such as liver problems. Patients should ensure that they understand the potential risks of using this treatment in relation to the benefits of treatment before receiving the injection.

Promethazine may also be prescribed for the treatment of other conditions as directed by your doctor.