Comparison between Bupivacaine and Ropivacaine

Table 1: Comparison between Bupivacaine and Ropivacaine

	Bupivacaine	Ropivacaine
Description [1]	Amide	Amide
Relative Potency [1]	8	6
Onset [1]	10 – 15 mins	10 – 15 mins
Duration [1] (without Epinephrine)	3 – 12 h	3 – 12 h
Duration [1] (with Epinephrine)	4 – 12 h	4 – 12 h
Maximum dose [1] (without Epinephrine)	2.0 mg/kg	3.0 mg/kg
Maximum dose [1] (with Epinephrine)	2.5  mg/kg	4.0 mg/kg
ADRs	More cardiotoxic [1] (hypotension & bradycardia) [2] GI disorders: nausea, vomiting, Renal & urinary disorders (retention or incontinence), postdural puncture headache. [2]	Less cardiotoxic with better safety margin. [1] Vascular disorder (hypotension), nausea, vomiting, urinary retention, hyperthermia, rigor, backpain, hypertension, bradycardia, tachycardia, paraesthesia, dizziness, headache. [4]
Pharmacokinetics	Muscular relaxation of lower extremities last 2-2.5 h. Blockage of abdominal muscle lasts 45- 60 mins. [3]	Exhibits complete & biphasic absorption from epidural space with half lives of the two phases of the order as 14 mins and 4 h for adults. Renal Cl: 1 ml/min Total plasma clearance: 440 ml/min Vd: 47 L, Terminal half life: 1.8 h after IV Excretion: 86% urine Slow absorption is the rate limiting factor which explains why the apparent elimination half life is longer after epidural than after IV administration. [4]
Pharmacodynamics	Long acting with moderate muscular relaxation of lower extremities. Allows motor blockade of the abdominal muscles. Bupivacaine heavy is hyperbaric and its initial spread in the intrathecal space is affected by gravity. [3]	Has anaesthetic and analgesic activity. At high doses: surgical anaesthesia Lower dose: sensory block with limited and non-progressive motor block. [4]
Storage	Do not store above 250C  for unopened vial [3]	Do not store above 30 o C. Do not freeze
Stability	Discard unused solution [3]	Discard any unused solution [4]
Incompatibilities	N/A	Precipitates in alkaline solution with pH>6 [4]

 References: 

1.     http://www.frca.co.uk/article.aspx?articleid=100816
2.     http://e-safe-anaesthesia.org/e_library/09/Subarachnoid_Block_TOTW_059_2007.pdf
3.     https://www.medicines.org.uk/emc/medicine/185#EXCIPIENTS
4.     https://www.medicines.org.uk/emc/medicine/7290