A major but rare side-effect of carbapenems is neurotoxicity. It can range from seizures to non-seizure toxicity (agitation, hallucination, delirium, etc.) It is estimated that carbapenem-induced seizure is most with imipenem-cilastin (3-33%) , but the remaining (doripenem, meropenem, ertapenem) have a prevalence of less than 1%. Seizure as an adverse drug reaction is highly documented. On the other-hand, non-seizure toxicity (hallucinations, agitation) has limited information. There is no established prevalence rate due to a small population of patients documented from post-marketing surveillance. However, generalized altered mental status due to ertapenem has a prevalence of 3.1 to 5.3% . A prescribing cascade refers to the situation when a new medicine is prescribed to 'treat' an adverse reaction to another drug due to the belief that a new medical condition requiring treatment has developed . Prescribing cascade can result to adverse outcomes. It is possible that the second drug will increase the severity of the adverse reaction to the first drug or when the second drug places the patient at risk of additional adverse drug reactions.