I found this while searching for something else, on Google and thought you might find it interesting.
From the Peoria Humane Society website: Melatonin the Marvelous!!!
Amazingly, an effective treatment for thunderstorm and noise phobias may be an over-the-counter hormone used by humans to prevent insomnia. Melatonin, which is produced by the pineal gland, sets the body’s internal clock in response to exposure to light. The body creates melatonin only in total darkness (the pineal gland stops production when any part of the body, even the back of the leg, is exposed to light). In humans, melatonin has been shown to calm the nerves, reduce anxiety, relieve panic disorders, prevent migraine headaches and facilitate deep sleep. In birds and other animals in the wild, melatonin levels trigger spring reproduction, fall migration, and winter hibernation. Actually, hibernation is what brought melatonin to dogs with thunderstorm/noise phobias.
Melatonin has helped some noise-phobic dogs go from being panicked to only mildly concerned with thunder or other loud noises such as fireworks and gunshots (it has not been found to be effective in other stressful...