Wood Lock is a Chinese medicated liniment/ointment (external analgesic) from Hong Kong. Its intended purpose is to relieve muscle aches and pains. It is highly popular in Hong Kong and sold in North America at Chinese herbalist stores.
Wood Lock has been made by the China Medicine Laboratory and Wood Lock Medicine Company Limited since 1968.
The liniment is based on the formula of the traditional White Flower Oil recipe, in which the creator, Wong To Yick, added several Chinese herbs including Dong Quai. In this sense, it can be considered of containing herbal extracts but it was never labelled.
This liniment has an unconventional form of application, using acupressure methods rather than the conventional massage; the oil is applied on the point of pain and finger pressure is then applied on the point for 15 minutes.
As of 1994-1996, the medicated liniment shipped to the United States of America was packaged in .85- and 1.7-fluid-ounce glass bottles with black plastic caps. The label contained a photo of a man's face as well as "WOOD LOCK Medicated Balm" in both English and Chinese writing.
It was recalled in the United States of America on November 19, 1996 because of incorrect packaging that could result in children ingesting the poisonous Methyl Salicylate ingredient, resulting in severe injury or death.