类视黄醇
有证据表明维生素 A 和倍他胡萝卜素可消退白斑，而维甲酸可预防异常增生进一步恶化。但这些数据仅基于少数患者，且不良反应较常见，在停止治疗后容易复发。[125]Hong WK, Endicott J, Itri LM, et al. 13-cis-retinoic acid in the treatment of oral leukoplakia. N Engl J Med. 1986;315:1501-1505.http://www.ncbi.nlm.nih.gov/pubmed/3537787?tool=bestpractice.com[126]Sankaranarayanan R, Mathew B, Varghese C. Chemoprevention of oral leukoplakia with vitamin A and beta carotene: an assessment. Oral Oncol.1997;33:231-236.http://www.ncbi.nlm.nih.gov/pubmed/9307711?tool=bestpractice.com[127]Stich HF, Hornby AP, Mathew B, et al. Response of oral leukoplakias to the administration of vitamin A. Cancer Lett. 1988;40:93-101.http://www.ncbi.nlm.nih.gov/pubmed/3370632?tool=bestpractice.com近期一篇关于使用局部免疫调节剂（例如异维 A 酸凝胶）调节或控制白斑中异常增生的综述显示，这类疗法并不是对所有病例都有效。[128]Elad S, Epstein JB, von Bültzingslöwen I, et al. Topical immunomodulators for management of oral mucosal conditions, a systematic review. Part II: miscellaneous agents. Expert Opin Emerg Drugs. 2011;16:183-202.http://www.ncbi.nlm.nih.gov/pubmed/21244328?tool=bestpractice.com
植物化合物
Bowman-Birk 型胰蛋白酶抑制剂 (BBI) 是一种从大豆中分离得到的丝氨酸蛋白酶抑制剂，研究报道，该药物在口腔白斑的治疗中取得了较好的效果。[129]William WN Jr, Papadimitrakopoulou VA. Optimizing biomarkers and endpoints in oral cancer chemoprevention trials. Cancer Prev Res (Phila). 2013;6:375-378.http://www.ncbi.nlm.nih.gov/pubmed/23639861?tool=bestpractice.com
