If you have a mouth ulcer and need to take vitamin supplements, then you can take vitamin b, vitamin b2, vitamin c, etc. Deficiencies of these vitamins in the body can lead to recurrent mouth ulcers. Oral ulcers are the most common diseases of the oral mucosa and generally occur on the tongue, cheek, gums and other locations of the oral mucosa. Oral ulcers are generally divided into traumatic ulcers and recurrent ulcers. For traumatic ulcers, the main thing is to remove the irritant causing the ulcer and then apply topical medication, which usually heals quickly. For recurrent ulcers, the cause is not very clear, so the cause needs to be identified and treated accordingly, and vitamin deficiency is only one of the causes. Generally ulcers are self-limiting, as long as you maintain good oral hygiene, remove local irritants and do not eat irritating things, the ulcers will heal on their own in seven to ten days. If an ulcer does not heal in more than 2 weeks, you need to go to the hospital for pathological examination to see if there are other lesions. For mouth ulcers caused by vitamin deficiency, it is still necessary to supplement the above vitamins so as to solve the problem of recurrent ulcers.