Final answer:
Jaundice and extrapyramidal symptoms are serious side effects that require immediate cessation of haloperidol, as they indicate potential liver dysfunction and movement disorder complications.
Step-by-step explanation:
When administering large doses of haloperidol, a potent antipsychotic medication, it is crucial for the nurse to be vigilant for certain clinical manifestations that could signal severe side effects warranting the immediate cessation of the drug. Among the listed options, jaundice and extrapyramidal symptoms are the most concerning. Jaundice could indicate a serious condition like drug-induced hepatitis, while extrapyramidal symptoms reflect serious movement disorders related to the medication's effects on the basal nuclei and its interference with dopamine activity.