Neo-Synephrine® is an over-the-counter nasal spray containing either phenylephrine or oxymetazoline, two similar drugs that act to temporarily relieve nasal congestion brought on by colds, flu or allergies. This medication is not meant for children younger than 4 years of age and should not be used for more than three days, because it may cause congestion to worsen. Some people may experience mild side effects such as burning and irritation, which may cause sneezing. People who are taking or have recently taken certain drugs should consult with their doctor before using Neo-Synephrine®.
Decongestants such as Neo-Synephrine® act by constricting the small blood vessels in the nose and sinuses, thereby reducing swelling and inflammation. This effect is temporary, lasting from four to 12 hours, depending on the product formulation. Overuse of this medication can lead to what is called "rebound" congestion, which is often worse than the original problem. People sometimes develop an addiction to Neo-Synephrine®, using more and more of the drug in an effort to clear their nasal passages. To avoid this problem, it is advised that consumers limit their use of the product to a few days.
Patients using any prescription drugs should check with their doctor to make sure there will be no interaction between their medications and Neo-Synephrine®. Those taking medications for high blood pressure, heart disease, diabetes or urinary tract disorders may run the risk of drug interactions. Neo-Synephrine® has been known to interact with drugs used to treat insomnia, anxiety, depression and bipolar disorder, as well. This product should not be used in conjunction with other decongestants or by anyone who is allergic to phenylephrine.
Pregnant or breastfeeding women should avoid using Neo-Synephrine®, because both of the active ingredients used in the various formulations are considered Category C drugs, meaning they either have had adverse effects on the fetuses of laboratory animals or have not been tested on either animals or humans. Both phenylephrine and oxymetazoline constrict blood vessels, so it is theorized that they may also restrict blood flow to the uterus. It is unknown whether these chemicals pass into breast milk, so nursing mothers also are advised not to use this product.
Symptoms such as dizziness, anxiety, vomiting and sweating may indicate a Neo-Synephrine® overdose. Medical attention should be sought immediately, because symptoms could progress to breathing problems, erratic heart rate or convulsions. As should any medication, this product should be kept out of the reach of children and pets.