Anticholinergic Drugs

A 68-year-old man with Parkinson's disease is started on benztropine for tremor and rigidity. Which of the following is the most common reason for discontinuation of anticholinergic therapy in elderly patients?

A 55-year-old woman with a history of peptic ulcer disease and gastroesophageal reflux presents with excessive salivation and drooling due to advanced Parkinson's disease. She requires an anticholinergic agent that will reduce salivary secretion without worsening her gastrointestinal symptoms. Which drug is most appropriate?

All of the following are true regarding anticholinergic drugs EXCEPT:

Which of the following anticholinergic drugs is a tertiary amine and therefore crosses the blood–brain barrier?

A 68-year-old man with Parkinson's disease presents with severe resting tremor and rigidity that is inadequately controlled on levodopa monotherapy. He has no contraindications to anticholinergic agents. Which anticholinergic drug is the drug of choice for symptomatic relief of tremor and rigidity in this patient?