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Neo-Synephrine Nasal

Generic name: phenylephrine nasalFEN-il-EFF-rin ]
Brand names: 4-Way, 4-Way Menthol, Little Noses Decongestant, Nasal Four, Neo-Synephrine Extra Strength Nasal, ... show all 10 brands
Drug class: Nasal antihistamines and decongestants

Medically reviewed by Drugs.com on Aug 8, 2023. Written by Cerner Multum.

What is Neo-Synephrine Nasal?

Phenylephrine is a decongestant that shrinks blood vessels in the nasal passages. Dilated blood vessels can cause nasal congestion (stuffy nose).

Neo-Synephrine Nasal is used to treat nasal congestion and sinus pressure caused by allergies, the common cold, or the flu. Phenylephrine may be used to treat congestion of the tubes that drain fluid from your inner ears, called the eustachian (yoo-STAY-shun) tubes.

Neo-Synephrine Nasal may also be used for purposes not listed in this medication guide.

Neo-Synephrine Nasal side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Neo-Synephrine Nasal may cause serious side effects. Stop using Neo-Synephrine Nasal and call your doctor at once if you have:

Side effects may be more likely in older adults.

Common side effects of Neo-Synephrine Nasal may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Warnings

Do not use Neo-Synephrine Nasal if you have used an MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, or tranylcypromine.

Before taking this medicine

You should not use Neo-Synephrine Nasal if you are allergic to it.

Do not use Neo-Synephrine Nasal if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, tranylcypromine, and others.

Ask a doctor or pharmacist if it is safe for you to use this medicine if you have other medical conditions, especially:

It is not known whether Neo-Synephrine Nasal will harm an unborn baby. Do not use this medicine without a doctor's advice if you are pregnant.

It is not known whether phenylephrine nasal passes into breast milk or if it could harm a nursing baby. Do not use this medicine without a doctor's advice if you are breast-feeding a baby.

How should I use Neo-Synephrine Nasal?

Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended. Cold medicine should be used only for a short time until your symptoms clear up.

Do not give Neo-Synephrine Nasal to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.

Neo-Synephrine Nasal is usually used every 4 hours. Follow the directions on the medicine label. Never use more of this medicine than directed on the label or prescribed by your doctor. Using this medicine too long can damage the lining of your nasal passages and lead to chronic nasal congestion.

To use the nasal spray:

After each use, clean the tip of the spray bottle with a clean tissue or rinse it with hot water, making sure that no water gets into the medicine bottle. Keep the cap on the bottle when not in use.

To use the nasal drops, lie on your back with your head tilted back. Insert the correct number of drops and remain lying in this position for several minutes. Gently turn your head from side to side.

To prevent the spread of infection, do not share Neo-Synephrine Nasal with anyone else.

Call your doctor if your symptoms do not improve after 3 days of treatment, or if you have a fever with a headache, cough, or skin rash.

If you need surgery, tell the surgeon ahead of time that you are using Neo-Synephrine Nasal. You may need to stop using the medicine for a short time.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Since Neo-Synephrine Nasal is used when needed, you may not be on a dosing schedule. If you are on a schedule, use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include severe dizziness or drowsiness, slow heart rate, and fainting.

What should I avoid while using Neo-Synephrine Nasal?

Avoid getting Neo-Synephrine Nasal in your eyes.

Ask a doctor or pharmacist before using any other cold, cough, or allergy medicine. Many combination medicines contain pseudoephedrine. Taking certain products together can cause you to get too much of this medicine.

What other drugs will affect Neo-Synephrine Nasal?

Ask a doctor or pharmacist before using this medicine if you are also using any other drugs, including prescription and over-the-counter medicines, vitamins, and herbal products. Some medicines can cause unwanted or dangerous effects when used together. Not all possible interactions are listed in this medication guide.

Ask a doctor or pharmacist if it is safe for you to use Neo-Synephrine Nasal if you are also using any of the following drugs:

This list is not complete. Other drugs may interact with phenylephrine nasal, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.