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Uses

What is promethazine/phenylephrine used for?

Promethazine/phenylephrine is commonly used to reduce nasal congestion and other symptoms from allergies or common cold.

Promethazine/phenylephrine may also be used for other conditions as determined by your healthcare provider.

How does promethazine/phenylephrine work (mechanism of action)?

Promethazine works by blocking certain histamine receptors in the body, which helps to reduce runny nose, sneezing, congestion, and other symptoms. Phenylephrine helps reduce nasal congestion by making the blood vessels inside the nose smaller.

How is promethazine/phenylephrine supplied (dosage forms)?

Brands and other names

  • Phenergan VC
  • Prometh VC
  • Promethazine VC

Dosage forms and strengths

  • 6.25 mg/5 mg per 5 mL oral solution

How should I store promethazine/phenylephrine?

Promethazine/phenylephrine should be stored at room temperature, between 68 F to 77 F (20 C to 25 C). It can be exposed to temperatures between 59 F to 86 F (15 C to 30 C) for shorter periods of time, such as when transporting it. Store in a cool, dry place.

Side Effects

What are the most common side effects of promethazine/phenylephrine?

The most common side effects of promethazine/phenylephrine are listed below. Tell your healthcare provider if you have any of these side effects that bother you.

  • Drowsiness or dizziness
  • Confusion or blurred vision
  • Restlessness, anxiety, or insomnia 
  • Changes in blood pressure or heart rate
  • Dry mouth
  • Weakness or tremor
  • Nausea or vomiting

There may be other side effects of promethazine/phenylephrine that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of promethazine/phenylephrine?

While less common, the most serious side effects of promethazine/phenylephrine are described below, along with what to do if they happen.

Severe Allergic Reactions. Promethazine/phenylephrine may cause allergic reactions, which can be serious. Stop taking promethazine/phenylephrine and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Breathing Problems. Promethazine/phenylephrine may cause slow or shallow breathing, especially if you have breathing problems from another condition or take other medicines that can slow your breathing. Tell your healthcare provider if you develop severe sleepiness or trouble breathing, especially when you start promethazine/phenylephrine. Stop taking promethazine/phenylephrine and get emergency help if you have any of the following symptoms.

  • Changes in the color of your skin, including bluish color to your lips and fingernails
  • Confusion
  • Shortness of breath
  • Feeling dizzy, lightheaded, or fainting
  • Changes in your heart rate or rhythm, such as a fast, slow, pounding or skipping heartbeat
  • Slow or shallow breathing
  • Excessive sleepiness or trouble staying awake

Seizures. Promethazine/phenylephrine may cause seizures, especially if you have a seizure disorder. There are many different types of seizures and some of them are not easy to recognize. Stop taking promethazine/phenylephrine and call your healthcare provider if you have any of the following signs that a seizure is happening or could happen.

  • Muscle twitching, jerking, spasms, tremors, or other uncontrolled movements
  • Stiffening of your arms and legs
  • Feeling anxious, nervous, confused, or a sense of dread
  • Feeling dizzy or lightheaded
  • Falling or losing consciousness

Bone Marrow Suppression. Promethazine/phenylephrine may cause your bone marrow to not make enough cells. This can lead to low blood levels of important cells, such as red blood cells, white blood cells, platelets, and neutrophils. Bone marrow suppression can lead to infections or bleeding. This can be serious or even life-threatening. Keep all appointments to have your blood checked. Tell your healthcare provider right away if you have any of the following symptoms of bone marrow suppression.

  • Fever
  • Shortness of breath
  • Pale or yellowish skin
  • Easy bruising or bleeding
  • Frequent infection
  • Unusual weakness or tiredness
  • Dizziness, lightheadedness, or feeling like you are about to pass out
  • Headache
  • Fast or abnormal heartbeat

Neuroleptic Malignant Syndrome (NMS). Promethazine/phenylephrine can cause a rare but serious condition called neuroleptic malignant syndrome. NMS is a serious condition that can lead to death. Stop taking promethazine/phenylephrine and call your healthcare provider right away if you have any of the following symptoms.

  • High fever
  • Muscle stiffness or rigidity, where it is hard to move
  • Changes in your breathing or heart rate
  • Increased sweating
  • Confusion

Movement Problems. Promethazine/phenylephrine may rarely cause involuntary movement problems, including shakiness, stiffness, or jerkiness. Call your healthcare provider right away if you develop any unusual or uncontrolled movements. 

Warnings & Precautions

Who should not use promethazine/phenylephrine?

Allergies to Ingredients. People who are allergic to any of the following should not take promethazine/phenylephrine.

  • Promethazine
  • Phenylephrine
  • Phenergan VC
  • Prometh VC
  • Promethazine VC
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in the specific promethazine/phenylephrine products they stock.

Lung Problems. Promethazine/phenylephrine should not be used if you have asthma or other lung problems. Promethazine/phenylephrine can make these conditions worse.

High Blood Pressure (Hypertension). Promethazine/phenylephrine should not be used if you have high blood pressure. Promethazine/phenylephrine could make this condition worse.

Peripheral Vascular Disease. Promethazine/phenylephrine should not be used if you have peripheral vascular disease, which is a condition that affects blood vessels. Promethazine/phenylephrine could make this condition worse.

Drug Interactions. Promethazine/phenylephrine should not be taken while you are using certain other medicines. Before taking promethazine/phenylephrine, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using or have used recently. See the Interactions section for more details.

Children. Promethazine/phenylephrine should not be used in any child younger than two years of age. Slow or shallow breathing that can lead to death may occur. 

What should I know about promethazine/phenylephrine before using it?

Do not take promethazine/phenylephrine unless it has been prescribed to you by a healthcare provider. Take it as prescribed.

Do not share promethazine/phenylephrine with other people, even if they have the same condition as you. It may harm them.

Keep promethazine/phenylephrine out of the reach of children.

Use an accurate measuring device to measure your dose of promethazine/phenylephrine. A household spoon is not an accurate measuring device and may cause you to take the wrong dose. Ask your pharmacist to recommend an appropriate measuring device.

Promethazine/phenylephrine can affect your alertness or coordination. Do not drive or do other activities that require alertness or coordination until you know how promethazine/phenylephrine affects you.

Promethazine/phenylephrine can make your skin more sensitive to light from the sun, sunlamps, and tanning beds. This is called photosensitivity. Exposure to this light can cause severe sunburns, blisters, and swelling. If you need to be in sunlight, wear sunscreen, a hat, and clothing that covers your skin.

People who are 65 and older can be at greater risk for some side effects from promethazine/phenylephrine. Talk to your healthcare provider about your risks if you are in this age group.

Promethazine/phenylephrine may cause some laboratory tests to give false readings, including pregnancy tests and blood sugar tests. Talk to your healthcare provider if you have any concerns.  

What should I tell my healthcare provider before using promethazine/phenylephrine?

Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if promethazine/phenylephrine is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions. Tell your healthcare provider if you have any of the following. 

  • Breathing problems, such as asthma or chronic obstructive pulmonary disease (COPD)
  • Sleep apnea
  • Seizures
  • Diabetes
  • Liver, kidney, or thyroid problems
  • Heart or circulation problems 
  • Problems peeing 
  • Bladder or prostate problems 
  • Stomach or bowel problems
  • Glaucoma 

Pregnancy. It is not known if or how promethazine/phenylephrine could affect pregnancy or harm an unborn baby. Tell your healthcare provider if you are or plan to become pregnant. Your healthcare provider will advise you if you should take promethazine/phenylephrine while you are pregnant or trying to get pregnant.

Breastfeeding. It is not known if promethazine/phenylephrine passes into breast milk. Tell your healthcare provider if you are breastfeeding or plan to breastfeed. Your healthcare provider will advise you if you should take promethazine/phenylephrine while breastfeeding.

Interactions

Does promethazine/phenylephrine interact with foods or drinks?

There are no known interactions between promethazine/phenylephrine and foods or non-alcoholic drinks.

It is unknown if drinking alcohol will affect promethazine/phenylephrine. The risk of drowsiness and dizziness may be increased if you drink alcohol while taking promethazine/phenylephrine.

Does promethazine/phenylephrine interact with other medicines (drug interactions)?

Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any of the following before taking promethazine/phenylephrine.

  • A monoamine oxidase inhibitor (MAOI) within the past 2 weeks, which is a medicine usually used for depression or Parkinson’s disease
  • A tricyclic antidepressant, such as amitriptyline, nortriptyline, or protriptyline, even if it is not used for depression
  • A barbiturate, such as phenobarbital, butalbital, or primidone, which is a medicine that may be used to treat insomnia, migraines, or seizures
  • Any other medicine that causes dizziness and sleepiness, such as prescription pain medicines, sleep medicines, and medicines for anxiety
  • Amphetamine, which is a stimulant medicine that may be used as an appetite suppressant 
  • Epinephrine, which is a medicine that is commonly used to treat severe allergic reactions or low blood pressure in emergency situations
  • An anticholinergic medicine, which includes antihistamines and medicines commonly used for overactive bladder, Parkinson’s disease, or stomach problems
  • An ergot, such as ergotamine (Ergomar) or dihydroergotamine (Migranal or Trudhesa), which is a medicine used to treat migraine
  • A beta-blocker, such as metoprolol (Lopressor, Toprol XL, and others), atenolol (Tenormin), or propranolol (Inderal LA, Innopran XL), which is a medicine that may be used for certain heart conditions or to reduce blood pressure
  • An alpha-blocker, such as terazosin, doxazosin, alfuzosin, or prazosin, which is a medicine that may be used for high blood pressure and/or difficulty peeing due to an enlarged prostate

Many other medicines may alter the blood levels of promethazine/phenylephrine. Tell your healthcare provider about all medicines that you take or have recently taken.

This may not be a complete list of medicines that can interact with promethazine/phenylephrine. Always check with your healthcare provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much promethazine/phenylephrine?

If you or someone else has used too much promethazine/phenylephrine, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of promethazine/phenylephrine?

If you miss a dose, skip the missed dose and only take the next dose at your usual time. Do not take double or extra doses.