Final answer:
The patient with acute drooping of the right upper eyelid and double vision likely has myasthenia gravis, which is characterized by muscle weakness and is associated with abnormal communication between nerves and muscles.
Step-by-step explanation:
The symptoms described, including acute drooping of the right upper eyelid (complete ptosis) and double vision (diplopia) upon manual elevation of the lid, are suggestive of a neurological disorder. Based on the information provided and the keywords related to acetylcholine and muscle weakness, the diagnosis could likely be myasthenia gravis. Myasthenia gravis is characterized by muscle weakness that often starts in the muscles controlling eye and eyelid movement, resulting in ptosis and diplopia. The symptoms typically worsen with muscle use and improve with rest. Myasthenia gravis is associated with abnormal communication between nerves and muscles, often due to an autoimmune process that involves the production of antibodies against acetylcholine receptors at the neuromuscular junction.