At a pharmaceutical factory in Chengdu, China, an order that Thomas Leung placed from Manhattan in January is sitting on hold.

The shipment includes a variety of concentrated herbal granules used in traditional Chinese medicine. There’s dang gui, also known as angelica root, which is used to treat gynecological ailments; chai hu, or bupleurum root, an herb that is often used to calm nerves; and huang qi, or astragalus root, a tonic herb that promotes immune strength.

It is not clear when the shipment will land at Kamwo Meridian Herbs, a New York City staple for more than half a century that claims to be the largest traditional Chinese medicine dispensary on the East Coast. When it arrives, the herbs will be dispensed to practitioners and patients looking to treat colds, pain and other ailments — but for now, the herbs must sit.

Dr. Leung, Kamwo’s chief executive, put a stop on the order after President Trump placed a minimum tariff of 145 percent on all Chinese goods last month. China responded by raising tariffs on U.S. goods to 125 percent, and the resulting standoff has effectively frozen trade between the two countries.

Traditional Chinese medicine is just one of many industries that has been upended by the tariffs and the uncertainty over when, or whether, they may be lifted. Already, fewer ships are arriving in American ports, and consumers could begin seeing empty shelves by early June.