Red bumps on one side of the tongue may be caused by papillitis of the tongue, oral warts, herpes of the tongue, tongue ulcers and other diseases. 1. papillitis of the tongue: if the oral hygiene is poor or resistance is reduced, it is easy to cause bacteria or viruses to invade, causing papillitis of the tongue, appearing on one side of the tongue with red bumps. 2. Oral warts: If your partner suffers from warts, oral sex and other high-risk sexual behaviors can cause the oral cavity to be infected with human papillomavirus, resulting in red pimples the size of a grain of rice on one side of the tongue. 3. tongue herpes: when the patient suffers from tongue herpes disease, it may be caused by viral infection, will be prone to small herpes on the tongue, causing the phenomenon of red bumps on the side of the tongue. 4. Tongue ulcer: red bumps on one side of the tongue can also be caused by a tongue ulcer. An ulcer is a small white spot in the center, and when the ulcer is congested with blood, small red spots appear. Patients with red bumps on one side of the tongue should go to the hospital in a timely manner to clarify the cause of the disease and follow the doctor’s instructions for standardized treatment.