Department of Pharmacy Practice and Science, College of Pharmacy, University of Arizona, Tucson, AZ, USA.
Department of Pharmacy Practice, College of Pharmacy, Midwestern University, Glendale, AZ, USA.
Am J Health Syst Pharm. 2022 Jul 22;79(15):1236-1244. doi: 10.1093/ajhp/zxac058.
To discuss the potential implications of obesity for drug administration and absorption from subcutaneous (SC) and intramuscular (IM) injection sites.
The SC and IM routes are useful for the parenteral administration of medications to optimize pharmacokinetic properties such as time to onset and duration of effect, for cost considerations, or for ease of administration, such as when intravenous access is unavailable. The choice of SC or IM injection depends on the specific medication, with SC administration preferred for products such as insulin where a slower and more sustained response is desirable, while IM administration is usually preferred for products such as vaccines where more rapid absorption leads to a more rapid antibody response. Obesity has the potential to influence the rate and extent of absorption, as well as adverse effects, of medications administered by the SC or IM route through changes in SC tissue composition and depth or by inadvertent administration of IM medications into SC tissue because of improper needle length. Potential adverse effects associated with IM or SC injections in addition to pain, bruising, and hematoma formation include sciatic nerve injury, particularly with IM injection in the upper outer quadrant of the buttock; bone contusion or rarely osteonecrosis if the IM injection is excessively deep; and granulomas, fat necrosis, and calcification with SC injection.
Issues related to medication absorption in obese patients are likely to become more prominent in the future with increasing approvals of a wide range of biotherapeutic agents administered by SC injection. Studies should be directed toward these and other agents to assist with dosing decisions in this challenging population.
讨论肥胖对皮下（SC）和肌肉内（IM）注射部位药物给药和吸收的潜在影响。
SC 和 IM 途径可用于通过注射给予药物，以优化药代动力学特性，例如起效时间和作用持续时间，这是出于成本考虑，或者为了便于给药，例如当无法进行静脉注射时。SC 或 IM 注射的选择取决于特定药物，对于需要更慢和更持续反应的药物（如胰岛素），首选 SC 给药，而对于需要更快吸收以产生更快抗体反应的药物（如疫苗），通常首选 IM 给药。肥胖可能通过改变 SC 组织成分和深度，或者由于不当的针头长度而意外将 IM 药物注入 SC 组织，从而影响 SC 或 IM 途径给药的药物的吸收速度和程度以及不良反应。除了疼痛、瘀伤和血肿形成外，与 IM 或 SC 注射相关的潜在不良反应还包括坐骨神经损伤，特别是在臀部外上象限进行 IM 注射时；如果 IM 注射过深，可能会发生骨瘀伤或罕见的骨坏死；SC 注射会导致肉芽肿、脂肪坏死和钙化。
随着越来越多的生物治疗药物通过 SC 注射获得批准，肥胖患者药物吸收相关问题在未来可能会更加突出。应该针对这些和其他药物进行研究，以协助在这一具有挑战性的人群中进行剂量决策。
