Small red particles on the tongue should be inflammation of the filiform head on the dorsal surface of the tongue. There are many kinds of papillae on the surface of the back of the tongue, such as filiform papillae, lobulated papillae, and contoured papillae. Each of these papillae has some taste buds, which can sense taste and transmit the taste impulse stimulation to the brain, and then form the taste sensation. The filiform papillae are most distributed in the dorsal mucosa of the tongue in the first 2/3 of the tongue, which are normally small and difficult to detect. If the filiform papillae are inflamed, they become small red granules on the dorsal mucosa of the tongue and are associated with some pain. In case of filiform papillitis, topical iodine glycerin or warm water can be used to apply heat and promote the absorption of inflammation.