To the Editor.—Dr. Shaw's hypothesis that sudden unexpected death in infancy results from obstruction of the nasal airway to obligate nose breathers (Amer J Dis Child119:416-418, 1970) is indeed intriguing. It is widely held that phenylephrine nose drops are contraindicated in young infants (less than 6 months of age) due to the rebound mucosal edema which follows their use. It would be interesting to know if any of Dr. Shaw's patients had received phenylephrine nose drops shortly before their death. Certainly if Dr. Shaw's hypothesis is correct, vigorous efforts should be made to warn physicians and parents of the danger of administering "decongestant" nose drops to young infants. Such a program may lead to a reduction in the mortality due to SUD.