What is Earliest drug used in acute angle closure glaucoma – and explain in detail?
Approach in acute congestive glaucoma 

Start i.v. mannitol or i.v. acetazolamide
When IOT starts falling, start topical pilocarpine or β-blocker (timolol).
Apraclonidine/latanoprost may be added.
Once i.o.t. is reduced, surgery is done.
Diamox is acetazolamide