White bumps the size of a small grain of rice on the outside of the lower lip may be caused by fat grains, acne, folliculitis and so on. 1. Fatty grains: Fatty grains may be caused by heredity, skin inflammation, long-term use of hormonal drugs and other factors. Beige and white particles will appear on the surface of the patient’s skin. If there are fat grains on the outside of the lower lip, white bumps the size of small rice grains will appear locally. 2. Acne: Acne is considered to be related to increased secretion of androgens, excessive secretion of sebaceous glands, abnormal keratinization of sebaceous gland ducts in hair follicles, microbial infections and other reasons. The patient’s skin surface will appear conical pimples, the tip of the pimples will be yellowish-white, so the patient has acne on the outer side of the lower lip, which will be manifested as white bumps the size of a small grain of rice. 3. Folliculitis: folliculitis is mainly caused by Staphylococcus aureus infection, if patients with folliculitis on the outside of the lower lip, there will be red papules, papules on top of the white pustules, so the patient appeared on the outside of the lower lip with white bumps the size of a grain of rice. It is recommended that patients with white bumps the size of a grain of rice on the outside of the lower lip need to consult a doctor in a timely manner, you can choose the appropriate measures for treatment under the guidance of the doctor.