Dimetapp is an over-the-counter cough and cold medication that contains two active ingredients – dextromethorphan and pseudoephedrine. It is used to temporarily relieve symptoms caused by the common cold, flu, allergies, and upper respiratory infections. Some of the symptoms that Dimetapp aims to alleviate include cough, nasal congestion, runny nose, sneezing, watery eyes, and fever.
What are the active ingredients in Dimetapp?
There are two active ingredients in Dimetapp that provide its therapeutic effects:
- Dextromethorphan – This is a cough suppressant that belongs to the class of drugs called antitussives. It helps control coughs by acting on the cough center in the brain.
- Pseudoephedrine – This is a decongestant that constricts blood vessels in the nasal passages. This helps relieve nasal congestion and sinus pressure caused by colds, allergies, and upper respiratory infections.
By combining these two ingredients, Dimetapp treats two of the most bothersome symptoms associated with colds and allergies – cough and nasal congestion.
What are the uses and indications of Dimetapp?
Dimetapp is typically used for the temporary relief of the following cold and allergy symptoms:
- Coughing
- Stuffy, runny nose
- Sneezing
- Watery eyes
- Fever
- Nasal congestion
- Sinus pressure
- Minor aches and pains
It is suitable for adults and children above 6 years old. The regular Dimetapp formulations are not recommended for children below 2 years old, but Dimetapp Infant Drops are available for kids between 2-5 years old.
What are the dosage forms and strengths of Dimetapp?
Dimetapp is available in several dosage forms and strengths:
- Dimetapp Cold & Cough Liquid – Contains 10mg dextromethorphan HBr and 30mg pseudoephedrine HCl per 10mL. For adults and children above 12 years old, the recommended dose is 20mL every 4 hours. Not recommended for children under 6 years.
- Dimetapp Cold & Cough DM Liquid – Contains 15mg dextromethorphan HBr and 30mg pseudoephedrine HCl per 10mL. For adults and children above 12 years old, the recommended dose is 20mL every 4 hours. Not recommended for children under 6 years.
- Dimetapp Cold & Allergy Liquid – Contains 10mg dextromethorphan HBr and 60mg pseudoephedrine HCl per 10mL. For adults and children above 12 years old, the recommended dose is 20mL every 4 hours. Not recommended for children under 6 years.
- Dimetapp Infant Drops – Contains 3.5mg dextromethorphan HBr and 2.5mg pseudoephedrine HCl per mL. For children 2-5 years old, the recommended dose is 1mL every 4 hours, not to exceed 4 doses in 24 hours.
- Dimetapp Cold & Allergy Chewables – Each tablet contains 5mg dextromethorphan HBr and 15mg pseudoephedrine HCl. For children 6-12 years old, the recommended dose is 2 tablets every 4 hours. Not recommended for children under 6 years.
- Dimetapp Cold & Sinus Caplets – Each caplet contains 30mg pseudoephedrine HCl. For adults and children above 12 years old, the recommended dose is 1 caplet every 4-6 hours as needed.
- Dimetapp Cold & Cough Caplets – Each caplet contains 30mg pseudoephedrine HCl and 15mg dextromethorphan HBr. For adults and children above 12 years old, the recommended dose is 1-2 caplets every 4-6 hours as needed.
How does Dimetapp work in the body?
The two active ingredients in Dimetapp work in different ways to relieve cold and allergy symptoms:
Dextromethorphan
Dextromethorphan is a cough suppressant that works centrally in the brain to inhibit the cough reflex. It binds to NMDA and sigma-1 receptors in the medulla region of the brain stem. This reduces activity in the cough center, which then decreases the urge to cough.
Pseudoephedrine
Pseudoephedrine is an alpha-adrenergic agonist that causes vasoconstriction (narrowing of blood vessels) in the nasal passage and sinus cavities. This helps decrease inflammation and nasal congestion. It also reduces swelling of the mucous membranes lining the sinuses, which allows drainage and breathing to improve.
By combining these two drugs, Dimetapp provides relief from both coughing and nasal congestion – two of the most troublesome cold and allergy symptoms.
What are the side effects of Dimetapp?
Some potential side effects of Dimetapp include:
- Drowsiness
- Dizziness
- Nervousness
- Nausea
- Vomiting
- Stomach pain
- Constipation
- Diarrhea
- Headache
- Loss of appetite
- Dry mouth
- Insomnia
- Restlessness
- Excitability especially in children
- Skin rash or redness
Dimetapp should not be used by people who have certain medical conditions or who are taking certain medications. It is important to consult a doctor before using it if you have:
- Heart disease
- High blood pressure
- Diabetes
- Glaucoma
- Prostate issues
- Hyperthyroidism
- Taking antidepressants like MAO inhibitors
- Taking other cough and cold medications
Is Dimetapp a controlled substance?
No, Dimetapp is not classified as a controlled substance in the United States. It is an over-the-counter medication that does not require a prescription.
The dextromethorphan component acts on opioid receptors in the brain, so it has the potential for abuse at very high doses. However, the amount of dextromethorphan present in standard therapeutic doses of Dimetapp is too low to produce euphoric effects or be habit-forming.
The pseudoephedrine in Dimetapp can be diverted and used illegally for manufacturing methamphetamine. Therefore, there are some limitations on purchasing pseudoephedrine-containing products like Dimetapp. For example, you may have to show ID and sign a registry when buying it from a pharmacy counter. However, with reasonable use as directed, Dimetapp does not have high abuse potential.
How should Dimetapp be stored?
Dimetapp should be stored according to the following guidelines:
- Keep it in the original container with the child-resistant cap tightly closed.
- Store at room temperature away from excess heat, moisture, and direct sunlight.
- Keep it out of reach of children and pets.
- Do not use Dimetapp after its expiration date.
- If a liquid form is accidentally frozen, it should be thrown away.
Properly stored, Dimetapp liquid is good for up to 2 years and Dimetapp caplets or tablets are good for up to 3 years. Discard any unused portions after these time periods.
Conclusion
Dimetapp is a common over-the-counter cough and cold medication made by Pfizer. It contains the cough suppressant dextromethorphan and the nasal decongestant pseudoephedrine. By working on the brain’s cough center and constricting blood vessels in the nose/sinuses, Dimetapp provides temporary relief from coughing, stuffy nose, and sinus congestion caused by colds, allergies, and respiratory infections. When used correctly, it is generally safe and effective. However, some side effects are possible and Dimetapp should be used with caution in certain medical conditions. It is not considered a controlled substance, but the pseudoephedrine component is sometimes illicitly diverted in methamphetamine production. With responsible use as intended, Dimetapp can be a helpful option for managing annoying cold and allergy symptoms.