What is this medicine?
DEXTROMETHORPHAN, DIPHENHYDRAMINE, and PHENYLEPHRINE (dex troe meth OR fan; dye fen HYE dra meen; fen il EF rin) is a cough suppressant, a histamine blocker, and a decongestant combination. It is used to treat the cough and congestion of allergies or colds. This medicine will not treat an infection.
What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:
- enlarged prostrate
- heart disease
- high blood pressure
- stomach ulcer
- taken medicines called MAO Inhibitors like Nardil, Parnate, Marplan, Eldepryl in the last 14 days
- thyroid disease
- trouble passing urine
- an unusual or allergic reaction to dextromethorphan, diphenhydramine, phenylephrine, other medicines, foods, dyes, or preservatives
- pregnant or trying to get pregnant
How should I use this medicine?
Take this medicine by mouth. Follow the directions on the prescription label. Shake well before use. Use a specially marked spoon or container to measure your dose. Household spoons are not accurate. Take your medicine at regular intervals. Do not take it more often than directed.
Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children as young as 2 years old for selected conditions, precautions do apply.
Patients over 60 years old may have a stronger reaction and need a smaller dose.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.
What may interact with this medicine?
Do not take this medicine with any of the following medications:
- amphetamine or other stimulant drugs
- ergot alkaloids like dihydroergotamine
- MAOIs like Carbex, Eldepryl, Marplan, Nardil, and Parnate
This medicine may also interact with the following medications:
- barbiturates like phenobarbital
- medicines for depression, anxiety, or psychotic disturbances
- medicines for sleep
- muscle relaxers
- other medicines for cold, cough, or allergy
What should I watch for while using this medicine?
Tell your doctor or health care professional if your symptoms do not start to get better or if they get worse.
You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.
This medicine can make you more sensitive to the sun. Keep out of the sun. If you cannot avoid being in the sun, wear protective clothing and use sunscreen. Do not use sun lamps or tanning beds/booths.
What side effects may I notice from receiving this medicine?
Side effects that you should report to your doctor or health care professional as soon as possible:
- allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
- anxiety, irritable, or excited
- breathing problems
- fast, irregular heartbeat
- problems with balance, walking, or speech
- trouble passing urine or change in the amount of urine
- unusually weak or tired
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
- constipation or diarrhea
- dry mouth, nose, or throat
- nausea, vomiting
- stomach upset
- trouble sleeping