对乙酰氨基酚（英语：Acetaminophen，也称扑热息痛（Paracetamol），简称APAP）是一种广泛使用的非处方止痛及退烧药。对乙酰氨基酚常用来缓解头痛及各种轻至中度疼痛，也是许多感冒药的成分之一。与鸦片类镇痛药联用时，对乙酰氨基酚可以缓解各种重度疼痛，如术后疼痛及癌症疼痛。 虽然对乙酰氨基酚可以用来治疗炎性疼痛，但是其并不是非甾体抗炎药（NSAID），因为其抗炎作用非常弱。

虽然按推荐剂量服用对乙酰氨基酚很安全，但是轻微过量即可能致命。与其他非处方镇痛药相比，对乙酰氨基酚在低剂量时较安全，但是高剂量时毒性明显更高。 对乙酰氨基酚是非那西丁和乙酰苯胺的活性代谢产物，两者皆为曾经经常使用的止痛药和退烧药。 然而，不同于非那西汀、乙酰苯胺及其复方药物，对乙酰氨基酚在治疗剂量下无致癌性。对乙酰氨基酚被分类为轻度止痛药。

Paracetamol, also known as acetaminophen or APAP, is a medication used to treat pain and fever. It is typically used for mild to moderate pain. There is poor evidence for fever relief in children. It is often sold in combination with other ingredients such as in many cold medications. In combination with opioid pain medication, paracetamol is used for more severe pain such as cancer pain and after surgery. It is typically used either by mouth or rectally but is also available intravenously. Effects last between two and four hours.