<prompt> Cis atracurium is better then atracurium because:-Less histamine releaseLess half lifeLow drug doseLow cost  <response>: Atracurium Cis-atracurium Mixture of cis-isomers Pure cis-isomer Histamine release No minimal release CVS unstable CVS stable Less potent Dose - 0.5-0.6mhkg More potent Dose - 0.1-0.2 mgkg - Cis-atracurium and atracurium are dependent on Hoffman elimination - Cis-atracuriums duration of action is more predictable because of spontaneous breakdown. Although atracurium undergoes similar elimination, it is less potent than cis-atracurium, so its breakdown product, laudanosine, is found in higher concentrations 