http://www.spasmodicdysphonia.us

Article - Caffeine
People with spasmodic dysphonia are advised to cut out caffeine.
Here are some sources and amounts.

Major sources of caffeine in the average diet.

Source Amount Caffeine mg.
Coffee Brewed 12 oz. 206
Coffee Instant 12 oz. 114
Coffee Espresso (one shot) 1 oz. 71
Coffee Double Latte 2 oz. 142
Coffee Brewed Decaf 12 oz. 4
Coffee Instant Decaf 12 oz. 3
Tea Brewed 12 oz. 71
Tea Iced Lemon Flavor 12 oz. 39
Cocoa 12 oz. 11
Mountain Dew 12 oz. 55
Diet Coke 12 oz. 50
Coca-Cola Classic 12 oz. 45
Pepsi 12 oz. 37
Dr. Pepper 12 oz. 37
Bromoselzer 1 dose 32.5
Midol 1 dose 32
Dexatrim 1 dose 200
No-Doz 1 dose 100