Antihistamines are commonly found in many over-the-counter medications for cough and cold. They are particularly used as decongestants, and are effective at symptomatically clearing up runny noses. However, recent changes have occurred because of the side effects of these medications. Furthermore, though many of these drugs treat symptoms, they do not facilitate recovery. In 2011, the Food and Drug administration completed its review of these products and determined that they are no longer recommended for children under the age of 2.
Sedation and Confusion
The most notable side effect of antihistamines is sedation. This is more common in the older antihistamine medications that were commonly marketed as decongestants for infants. While the sedation may not be a major problem when given in the evening, it may cause drowsiness and inattention while the infant is awake as well. Antihistamines may also cause some degree of confusion and dizziness in infants due to their activity on the brain.
Other Side Effects of Antihistamines
Besides their effects on the brain, antihistamines have a number of other common side effects. These include mild fever, dryness of the mouth and stomach upset. Because antihistamines can temporarily weaken the muscles of the intestines and bladder, some infants may have constipation or pass urine less frequently. Antihistamines can also dilate an infant's pupils and cause blurring vision because of their effects on the muscles within the eye.
Large amounts of antihistamines can be dangerous, and because parents may give their infant multiple cold medications, the risk of toxicity in these infants is high. Infants who have consumed large amounts of antihistamines may be delirious and drowsy. The heart may lose its normal rhythm and beat in an abnormal pattern. Infants often have fever and may have breathing difficulties. These infants should be immediately taken to the emergency room for treatment of life-threatening complications.
Alternatives to Antihistamines
Because of the side effects of antihistamines, the FDA has determined that these medications are no longer safe in cold remedies for children under age 2. A number of alternatives are available which have more proven effectiveness. According to MayoClinic.com, infants with colds should be given plenty of fluids to prevent dehydration. Using a humidifier at home can also give some relief. Saline drops in the nose are useful to prevent congestion, and some studies have shown that zinc may be helpful. These alternatives can provide symptomatic relief for colds without the side effects of antihistamines.