对抗疗法是顺势疗法等替代疗法中对现代主流医学所使用的理论和治疗方法的称呼，指采取针对疾病本身的成因直接对抗、移除，使用药物的活性药物成份或物理操作（手术）等方法治疗疾病或伤势。“对抗疗法”一词首先由顺势疗法的创始人，塞缪尔·哈内曼在1810年提出。然而，主流医学界从未将这个术语作为正规的医学术语考虑。这个术语主要被各种替代疗法的用户使用，描述主流医学的理论和疗法，具有一定的贬义性质。世界卫生组织非正式发表的一份论文显示，在替代医学的使用环境下，“对抗疗法”可以用来指代大部分常用的医学手段，包括被称为“西医”、“生物医学”或“现代医学”的概念。

Allopathic medicine is an expression commonly used by homeopaths and proponents of other forms of alternative medicine to refer to mainstream medical use of pharmacologically active agents or physical interventions to treat or suppress symptoms or pathophysiologic processes of diseases or conditions. The expression was coined in 1810 by the creator of homeopathy, Samuel Hahnemann (1755–1843). In such circles, the expression "allopathic medicine" is still used to refer to "the broad category of medical practice that is sometimes called Western medicine, biomedicine, evidence-based medicine, or modern medicine" (see the article on scientific medicine).