WASHINGTON (AP) - Children under 4 should not be given cough and cold medicines, companies that make those products said Tuesday in announcing new guidelines for their use.

The industry has been criticized by pediatricians for marketing over-the-counter cough and cold remedies for children under 6 despite a lack of evidence that they work, and reports of safety problems.

Linda Suydam, president of the Consumer Healthcare Products Association, said the companies were voluntarily making the change "out of an abundance of caution." The association represents
leading manufacturers and distributors of nonprescription, over-the-counter medicines and nutritional supplements.

The companies will also add a warning to their product labels saying parents should not give young children antihistamines to make them sleepy. Antihistamines are used to relieve allergies.

Government health officials said last week the issue needed additional study.