Numbweed was a grass that grew on Pern. When boiled, it could numb any pain. It was used for both human and dragon injuries.
Making numbweed was a smelly process. The fumes could make eyes water.
During the Second Interval, numbweed was given to those suffering from the plague.
When Weyrwoman Moreta of Fort Weyr tended injured riders and dragons, she first coated her hands with oil so the numbweed wouldn't make her hands too numb for work.
In the Ninth Pass, when the Southern Weyr and Southern Hold were set up, a large plain of numbweed was given the name Numbweed Plain.
T'lion used numbweed on the injured dolphin Angie.