WASHINGTON — Bayer Healthcare is recalling 100,000 packages of Alka-Seltzer cold capsules because some do not properly display warning information about drowsiness.

The German conglomerate said today the issue affects less than 4 percent of packages from a single lot of Alka-Seltzer Plus Day & Night Liquid Gels.

As a result of the labeling issue, risk information about drowsiness does not appear on all packaging for the nighttime capsules. The product contains separately packaged capsules of both the day and night formulation. The night formula includes an antihistamine ingredient to help users get to sleep.

Company spokeswoman Tricia McKernan said the problem was caused by human error during the printing process. McKernan said the machinery used to make the labeling had to be shut down and manually restarted during the production for the affected lot.

The Alka-Seltzer day and night formula was distributed to pharmacies and other retailers nationwide. Stores have been advised to destroy products from the affected lot. Bayer stressed that the labeling issue does not affect any other Alka-Seltzer products.

Consumers who purchased packages from lot 296939L can contact Bayer for a refund at 1-800-986-3307. They should stop using the product immediately, Bayer says.