Phenylephrine + Chlorpheniramine + Dextromethorphan is an oral antihistamine, decongestant, and antitussive combinations. This medicine is used to prevent and treat conditions like:  

1. Common cold  
2. Dry cough and suppress the urge to cough. 
3. Allergic symptoms such as itching and watery eyes caused by histamine release      

1. Take this medicine exactly as prescribed by your doctor, at the same time each day. 
2. Do not stop taking this medicine without your doctor’s approval, even if you feel better. 
3. If you forget to take this medicine, take it as soon as you remember. If it’s almost time for your next dose, skip the missed dose.  

More Common  

1. Drowsiness or sleepiness 
2. Dizziness 
3. Dry mouth, nose, or throat 
4. Blurred vision 
5. Nausea or vomiting 
6. Constipation 
7. Headache 
8. Loss of appetite 
9. Restlessness or excitation     

Less Common

1. Allergic reactions (rash, hives, itching, swelling) 
2. High blood pressure symptoms (severe headache, dizziness, vision changes) 
3. Chest pain or fast heartbeat 
4. Confusion or anxiety 
5. Hallucinations 
6. Convulsions or seizures 
7. Urinary retention or difficulty urinating 
8. Blood disorders (thrombocytopenia, agranulocytosis) 
9. Serotonin toxicity 

Phenylephrine, Chlorpheniramine, and Dextromethorphan work together to relieve symptoms of cold and cough. Phenylephrine helps clear a blocked or stuffy nose by shrinking the swollen blood vessels in the nasal passages, making it easier to breathe. Chlorpheniramine reduces sneezing, runny nose, and watery eyes by blocking the effects of certain allergy-causing chemicals in the body. Dextromethorphan helps to control and reduce coughing by acting on the cough center in the brain. Together, they make breathing easier and help you feel more comfortable when you have a cold or allergies. 

Allergy/Hypersensitivity

If you have ever had an allergic reaction to Phenylephrine, Chlorpheniramine, Dextromethorphan (such as rash, itching, swelling, dizziness, or difficulty breathing), do not take this medicine. Inform your doctor before use. 

Heart problems or High Blood Pressure

If you have high blood pressure, heart disease, or irregular heartbeat, avoid this medicine because Phenylephrine can raise blood pressure and strain the heart. 

Liver Problems

If you have liver problems you should not take this medicine because Dextromethorphan and Chlorpheniramine are processed by the liver, which can make side effects worse. 

Glaucoma

If you have narrow-angle glaucoma, avoid using this medicine, as Chlorpheniramine can increase pressure inside the eyes. 

Overactive Thyroid (Hyperthyroidism)

Avoid this medicine if you have an overactive thyroid, as Phenylephrine can increase heart rate and cause palpitations. 

Asthma

If you have asthma, chronic cough, or other serious breathing problems, talk to your doctor before taking this medicine because Dextromethorphan may make it harder to clear mucus. 

Prostate Problems or Urinary Retention

Men with enlarged prostate or difficulty urinating should avoid this medicine, as Chlorpheniramine may worsen these symptoms. 

Skip heavy meals and grapefruit juice, which may affect how the medicine works. Avoid alcohol and too much caffeine, as they can cause dizziness or fast heartbeat. Drink plenty of water to stay hydrated and ease coughing. 

Avoid taking Phenylephrine + Chlorpheniramine + Dextromethorphan with the following medicines, as it may increase or decrease the desired effect, or in worse cases, it could be fatal: 

IUPAC (International Union of Pure and Applied Chemistry)/ Chemical name

Dextromethorphan: (1S,9S,10S)-4-methoxy-17-methyl-17-azatetracyclo[7.5.3.0 heptadeca-2(7),3,5-triene 

Chlorpheniramine: 3-(4-chlorophenyl)-N,N-dimethyl-3-pyridin-2-ylpropan-1-amine 

Phenylephrine: 3-[(1R)-1-hydroxy-2-(methylamino)ethyl] phenol 

Daily dose

Take Phenylephrine + Chlorpheniramine + Dextromethorphan exactly as your doctor recommends. The dose may change based on your condition and how well you respond. Do not take more than prescribed without consulting your doctor. 

Missed Dose

If you forget to take your medicine, take the medication as soon as you remember. If it’s nearly time for your next dose, skip the missed one and continue with your regular schedule. Always consult the doctor before making any changes to your dosage. 

Overdose

Do not take Phenylephrine + Chlorpheniramine + Dextromethorphan more than the prescribed dose per day. Overdosing may cause such as nausea, vomiting, stomach pain, dizziness, headache, low blood pressure, drowsiness, restlessness, or in rare cases, seizures and breathing difficulty. Seek immediate medical attention if any of these occur.  

1. Store the medicine at room temperature 
2. Keep away from sunlight and moisture 
3. Keep out of reach of children 

Phenylephrine + Chlorpheniramine + Dextromethorphan is a syrup that relieves cold, cough, and allergy symptoms. Phenylephrine works by clearing a blocked nose, Chlorpheniramine reduces sneezing, runny nose, and watery eyes, and Dextromethorphan calms coughing by acting on the brain. Common side effects can include drowsiness, dizziness, headache, fast heartbeat, or trouble sleeping, but serious problems are rare. Avoid alcohol and too much coffee, eat light meals, and drink plenty of water. Always follow your doctor’s advice and check before use if you have heart problems, high blood pressure, glaucoma, or allergies. 

What are the uses of Dextromethorphan, Phenylephrine, and Chlorpheniramine Maleate syrup? 

It is used to treat cough, cold, runny nose, sneezing, nasal congestion, and throat irritation caused by allergies or infections. 

What are the uses for chlorpheniramine maleate? 

It is used to relieve allergy symptoms such as runny nose, sneezing, watery eyes, and itching. 

How does dextromethorphan work? 

Dextromethorphan works by acting on the brain’s cough center to reduce the urge to cough. It doesn’t treat the cause of the cough but helps control frequent or irritating coughs, making it easier to rest and recover. 

Can dextromethorphan be taken during pregnancy? 

Only if prescribed by a doctor. It is generally considered low risk in recommended doses, but self-medication is not advised. Always consult your doctor before taking it while pregnant. 

What are the side effects of phenylephrine? 

Phenylephrine may cause increased blood pressure, fast or irregular heartbeat, nervousness, dizziness, headache, and trouble sleeping. Serious side effects are rare but more likely in people with heart problems or high blood pressure. Always take it as directed by your doctor. 

Which class of drug does phenylephrine belong to? 

Phenylephrine belongs to the decongestant class of drugs. It works by shrinking swollen blood vessels in the nose to relieve nasal congestion. 

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