However, one study suggested that it may interfere with maxillary sinus healing by reducing blood flow through the nasal passage. Xylomatazoline is similar to oxymetazoline, and studies indicate that it is has similar effects. The short-acting drugs naphazoline and tetrahydrozoline can stimulate the central nervous system and cause changes in blood pressure. In general, products with these ingredients should be avoided unless nothing else works. Phenylephrine is also short-acting but does not overstimulate the nervous system.
Pseudoephedrine has fewer stimulating effects than others.
Phenylpropanolamine is a stimulant and may cause changes in blood pressure. Some decongestants are combined with antihistamines, which are not useful for sinusitis caused by infection but can be helpful with people suffering from allergies who are experiencing symptoms of sinusitis. With prolonged use, nasal decongestants become ineffective. The tendency is to then increase the frequency of use to as often as once an hour. Withdrawal from the drugs after three to five days of over-frequent use causes symptoms of sinusitis and nasal congestion return'a phenomenon known as rebound effect.