It is associated with many conditions, including megaloblastic anemia from vitamin B12 deficiency, iron deficiency anemia (which in severe cases can lead to Plummer-Vinson syndrome) and oral candidiasis. It can also be a symptom of allergies, such as allergy to Balsam of Peru. Cheilitis can also be caused by taking the (retinoid) drug Isotretinoin. It may also be a pre-malignant lesion for squamous cell carcinoma.