Also known as “Mivacron”, Mivacurium is used to calm muscles during surgical procedures, or while on a ventilator. Remember that you should tell your doctor if you’re using other drugs, or if you have other health problems that might compromise the efficacy of Mivacurium. In fact, very bad and sometimes deadly allergic reactions have happened, albeit rarely, which is why it is important that you tell your doctor about any current or past health issues prior to taking Mivacurium. You should also tell them if you are pregnant or breastfeeding to fully understand the benefits and risks of using the medication in question. Bear in mind that Mivacurium is typically given as a shot into a vein, and this shot can also be given nonstop for a period of time. As far as the side effects are concerned, drugs.com mentions signs of an allergic reaction (such as hives, itching, and trouble breathing).