After taking antihistamines, some children may experience nightmares, unusual jumpiness or nervousness, restlessness or irritability. Decongestants Decongestants are used to treat nasal congestion and other symptoms associated with colds and allergies. They work by shrinking blood vessels, thereby decreasing the amount of fluid that leaks out and lessening nasal congestion. Many medications combine both antihistamines and decongestants to relieve a larger range of symptoms. Side effects of decongestants can include nervousness, sleeplessness or elevation in blood pressure.
Decongestants are also available in nose spray or drop form for acute congestion.
Prescription nasal sprays and drops do not have this effect and can be used for longer periods of time, as prescribed by your physician. People with asthma have inflamed airways. This inflammation causes the bronchi the main branches leading from the throat to the lungs to become overly reactive. The airways are more sensitive to various asthma triggers such as allergens, cold and dry air, smoke and viruses. Anti-inflammatory agents such as cromolyn , nedocromil and corticosteroids reduce inflammation and asthma symptoms.