Anaes · Local anaesthetic pharmacology

Local anaesthetic agents compared

Also known as Lidocaine bupivacaine ropivacaine comparison · Amide local anaesthetic head-to-head · Levobupivacaine and ropivacaine (safer S-enantiomers) · Local anaesthetic cardiotoxicity ranking

The amide local anaesthetics differ in onset, duration, potency and cardiotoxicity, and these four properties drive every exam answer on agent selection (textbook framework; exact doses per local formulary). Lidocaine (lignocaine) is the fast-onset, intermediate-duration versatile all-rounder and also a class Ib antiarrhythmic; lidocaine-prilocaine cream topical equivalence was studied in vitro by Shao et al. (2026) and lidocaine-tetracaine vs lidocaine-prilocaine pain scores were compared in a confounded retrospective microneedling analysis by Majewska et al. (2026). Bupivacaine is long-acting and potent but is taught as the MOST CARDIOTOXIC amide (textbook ranking; liposomal bupivacaine reported for nail procedures by Robinson et al., 2026, title-anchored, no abstract). Levobupivacaine and ropivacaine are the pure S-enantiomer alternatives taught as retaining long duration with less cardiotoxicity; ropivacaine-dexamethasone cortisol effects were measured in oral surgery by Stojanovic et al. (2026, n=90), continuous fascia iliaca block delirium was described in a 4-patient case series by Cao et al. (2026), and ESPB adjuvant comparison was reported by Grelowska et al. (2026, n=90 TKA). Prilocaine is short-acting and taught as low-toxicity per unit potency but causes methaemoglobinaemia via its o-toluidine metabolite, treated with methylene blue per local protocol. The taught cardiotoxicity ranking is bupivacaine greater than levobupivacaine or ropivacaine greater than lidocaine or prilocaine.