Carbapenems can only be given through an intravenous drip, which usually does not cause irritation at the injection site. If you have a severe allergy to penicillin, you generally should not be given a carbapenem. However, many patients with a mild or moderate allergy can tolerate carbapenems.
Alpha-1 adrenergic agonists. Alpha-1 adrenergic agonists stimulate alpha-1 receptors coupled to G proteins and phospholipase C. They can be classified in two groups: those which do not cross the blood-brain barrier and have peripheral effects and those which penetrate into the brain and have mainly central effects. Alpha-1 agonists with peripheral effects.
Agonists and Antagonists. Agonists are chemicals that mimic the action of a particular neurotransmitter. They bind to receptors and generate postsynaptic potentials. Antagonists are chemicals that block the action of a particular neurotransmitter. They bind to receptors but canât produce postsynaptic potentials. Because they occupy the receptor site, they prevent neurotransmitters from acting.