Central nervous system penicillin effects

What adverse central nervous system (CNS) effect can be seen with high dose intravenous administration of penicillin G ... 

During prolonged administration, penicillin drugs may also cause central nervous system (CNS) problems (e.g., confusion, hallucinations), as well as certain blood disorders, such as hemolytic anemia and thrombocytopenia. Other relatively minor side effects of penicillin drugs include gastrointestinal problems such as nausea, vomiting, and diarrhea. 

Adverse effects of the penicillins on the central nervous system include headache, dizziness, somnolence, confusion, tremor, and seizures. The penicillins can also adversely affect the liver, as evidenced by elevated liver enzymes and bilirubin, and the kidney, as evidenced by elevated blood urea nitrogen and creatinine. 

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