Final answer:
Anticholinergic drugs like Atropine, Diphenhydramine, and Chlorpheniramine can cause symptoms such as pinpoint pupils, blurred vision, headache, nausea, vomiting, diarrhea, sweating, muscle twitching, and more.
Step-by-step explanation:
Anticholinergic drugs such as Atropine, Diphenhydramine, and Chlorpheniramine have specific signs and symptoms. These can include miosis (pinpoint pupils), blurred/dim vision, headache, nausea, vomiting, diarrhea, copious secretions/sweating, muscle twitching/fasciculations, dyspnea, seizures, and unconsciousness. These symptoms are a result of the drugs' effects on the parasympathetic nervous system.