A child overdoses on a drug that affects both the autonomic and somatic nervous systems. As blood level of the drug rises he experiences hypertension and tachycardia, accompanied by skeletal muscle tremor. Further elevations of the drug cause all the expected signs and symptoms of autonomic ganglionic blockade, plus weakness and eventual paralysis of skeletal muscle. Which of the following drugs did the child most likely ingest?

A child overdoses on a drug that affects both the autonomic and somatic nervous systems. As blood level of the drug rises he experiences hypertension and tachycardia, accompanied by skeletal muscle tremor. Further elevations of the drug cause all the expected signs and symptoms of autonomic ganglionic blockade, plus weakness and eventual paralysis of skeletal muscle. Which of the following drugs did the child most likely ingest?

A 33-year-old woman becomes poisoned after receiving an injection of concentrated botulinum toxin. Which of the following is the main neurochemical mechanism by which this Clostridium toxin causes its effects?

78-year-old male with Parkinson's disease experiences Parkinson's worsening of his symptoms. He is already taking levodopa. Since the disease is characterized by degeneration of dopaminergic neurons, leading to the lack of inhibition of cholinergic neurons, the addition of which medication is likely to help alleviate the patient's symptoms?

Intravenous administration of epinephrine to a patient results in a severe decrease in diastolic pressure and an increase in cardiac output. Which of the following drugs might the patient have previously taken that could account for this unexpected effect?

All of the following are ß-adrenergic agonists EXCEPT: