Cialis (tadalafil) facts. Cialis is the trade name for a drug called Tadalafil. Cialis is one of a class of drugs known as PDE-5 (Phosphodiesterase type 5) inhibitors. Cialis and the other PDE-5 inhibitors can help men with erectile dysfunction (male impotence) by enhancing the erectile response when a man is sexually stimulated. Aside from Cialis, the other drugs in this class are Viagra (Sildenafil) and Levitra (Vardenafil).
This section shows a full list of all the diseases and conditions listed as a possible cause of Excessive yawning in our database from various sources. 1  Aortic dissection. 2  Excessive daytime sleepiness. 3  Heart attack.  Sleep apnea.
The evolution theory: Some think that yawning began with our ancestors, who used yawning to show their teeth and intimidate others. An offshoot of this theory is the idea that yawning developed from early man as a signal for us to change activities [source: University of Washington]. The boredom theory: Although we do tend to yawn when bored or tired, this theory doesn't explain why Olympic athletes yawn right before they compete in their event or why dogs tend to yawn just before they attack.