What is Dextromethorphan, diphenhydramine, and phenylephrine?
Dextromethorphan suppresses coughing. Diphenhydramine acts as an antihistamine. Phenylephrine works as a decongestant. Combination medicine that contains dextromethorphan, diphenhydramine, and phenylephrine can be used to treat allergies, flu, common colds, or coughs caused by the flu. Dextromethorphan, diphenhydramine, and phenylephrine do not treat coughs caused by asthma or emphysema, nor can they be used to treat those who smoke. This medication guide does not list all possible uses for dextromethorphan (also known as diphenhydramine), phenylephrine, or diphenhydramine.
Side Effects of Dextromethorphan, diphenhydramine, and phenylephrine
If you experience any of the following signs and symptoms of an allergic reaction: difficulty breathing, hives or swelling to lips, face, tongue or throat - seek medical assistance immediately!
This medicine can cause serious side effects. If you experience:
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Severe drowsiness;
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Urination that is painful or difficult
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Fast, pounding, or uneven heartbeats;
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Trouble breathing
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Confusion, anxiety, irritability, and tremors;
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A seizure;
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Problems with speech or balance
Side effects that may occur from dextromethorphan, diphenhydramine, and phenylephrine include:
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Dizziness, drowsiness, headache;
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Dry eyes and blurred vision
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Dry mouth, nose, or throat
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upset stomach, nausea, vomiting;
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Diarrhea, constipation;
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Tiredness and trouble sleeping.
There may be other side effects.Call your physician immediately if experiencing side effects; to report side effects directly with FDA call them on 1-800-FDA-1088 or fill out this online form.
Warnings
This medicine should not be taken within 14 days after having taken an MAO inhibitor medication. Examples include isocarboxazid or linezolid. Other examples are methylene blue injections, phenelzine, rasagiline, and selegiline. Follow the instructions on this medication. Too much diphenhydramine may cause serious heart problems, seizures, or even death. Do not use this medicine on a child under 4 years of age. Before using any other medication that contains diphenhydramine, consult your doctor or pharmacist. Overdosing on this medication can be fatal.
Before you take this drug
You should not take this medication if you've taken an MAO inhibitor in the last 14 days. A dangerous drug interaction may occur.MAO inhibitors include isocarboxazid (linezolid), phenelzine injections, rasagiline and selegiline; they may also include methylene blue injection.
Have any of the following conditions been present in your life:
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A cough that produces mucus
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Urination or prostate problems;
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High blood pressure, heart disease
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Diabetes;
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A thyroid disorder
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Glaucoma;
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A stomach ulcer.
This medication may contain phenylalanine.If you have phenylketonuria, take note of what medication the label lists. Before taking this medication while pregnant or nursing, always consult your healthcare provider first.
How to take Dextromethorphan, diphenhydramine, and phenylephrine?
Follow the directions on the label or from a physician regarding cold and cough medicines, taking only what is prescribed or until your symptoms subside. Do not exceed recommended amounts as too much diphenhydramine could lead to heart issues, seizures or even cause death. Be careful when giving medicine to young children; follow the directions on the label precisely, taking great care not to use antihistamines improperly as misusing these can result in sudden infant death syndrome and should only ever be given under direct medical guidance by an appropriately licensed provider. When giving antihistamines to infants under four years, always consult a pediatrician first! Measuring liquid medicine accurately is critical. Use either the dosing device provided, or another tool specifically made to measure doses like spoons would, when measuring liquid medicine. If symptoms don't improve within seven days or you experience fever, headache, cough or rash symptoms please call your healthcare provider immediately; notify him/her as well if any medical tests or surgeries will need to be scheduled after taking this medicine recently; store away from heat and moisture at room temperature to protect its efficacy.
What happens if I miss the dose?
You may not have a schedule for dextromethorphan, diphenhydramine, and phenylephrine because they are used as needed. If it is almost time for the next dose, skip any missed dose. Never take two doses in one go.
What happens if I overdose?
Call the Poison Help Line on 1-800-222-1222 if experiencing symptoms related to poisonous plants and seek emergency medical help as soon as possible. Overdose symptoms include confusion, vomiting, severe drowsiness, and ringing in the ears. Other symptoms are dry mouth and eyes, dilated pupils, rapid heartbeats, tremors, agitation, or hallucinations.
What should be avoided?
Do not drive or engage in hazardous activities until you have determined how the medicine will affect you. You may be unable to react properly. Before using any other medication that contains diphenhydramine, consult your doctor or pharmacist. You can use medicines to treat sleep problems, allergy symptoms, or skin itch. Too much diphenhydramine can lead to an overdose. Alcohol consumption can have side effects when taken with this medication.
Interaction with other drug
Before using dextromethorphan, diphenhydramine, or phenylephrine, consult your doctor or pharmacist. This is especially important if you are taking any other medications that may cause drowsiness, such as sleep medication, opioids, muscle relaxers, anxiety medicines, or seizure medicine.Inform your doctor of all medicines you are currently taking or have recently started or stopped taking, including all prescribed and nonprescribed drugs, vitamins and herbal products; this list may not cover every possible interaction.
