Old Wrinkly's Cures for Common Illnesses is a list of remedies for common illnesses written by Old Wrinkly. It appears in How to Cheat a Dragon's Curse, when Hiccup takes Fishlegs to see Old Wrinkly at the end of chapter five.
Stuff a small carrot up each nostril to stop a running nose. Remember to breathe through MOUTH.
Drink a cupful of live earwigs. The insects will probably attack the germs in your small intestine and eat them.
Paint the spots with Old Wrinkly's soothing lotion of Runny Seagull Poo. This will relieve the itching. It will also cause your friends to stay away from you, thus protecting them from infection.
Headache with Temperature
Old Wrinkly's tasty medicine of sheep mucus and dead flies wrapped in cobwebs will soon have the patient bouncing out of bed.
Pray to Thor. Nobody knows what to do with a virus.*
- Interestingly, 1,500 years later, medical science has advanced to such and extent, that we still don't know what to do with a virus.