Otolaryngologists and ENT physicians are the same. ENT=Ears, Nose, and Throat - Oto=ear, laryng=throat (the nose, or rhino, was dropped some years ago). Otolaryngologists go through 1 year of general surgery training and an additional 4-5 years of specialty head and neck surgery.
But many popular brands actually contain considerably less than an old-fashioned cup of black coffee. An 8.4-ounce serving of Red Bull, for instance, has a relatively modest 76 to 80 mg of caffeine, compared to the 95 to 200 mg in a typical cup of coffee, the Mayo Clinic reports.
The caffeine content in a cup of coffee is highly variable, ranging from 50 to 400+ mg per cup. A small home-brewed cup of coffee could contain 50 mg, while a big 16 oz Starbucks grande can contain over 300 mg. As a general rule, you can assume that an average 8 ounce cup of coffee contains around 100 mg of caffeine. Several sources suggest that 400 mg of caffeine, or 4 cups of coffee, are safe for most healthy adults (3, 5). However, many people (including myself) drink much more than that without any issues.