In order to treat Manic Depression, we have to take a look at the specific symptoms of this form of Depression that separates it from, and makes it different than, generalized Depression.
As the name suggests, Manic Depression is both sides of the energy spectrum.
This is why it is also associated with the name Bi-Polar disorder, though the Psychological establishment has decided that Manic Depression is a better descriptive phrase! So, this means that instead of being stuck with "the blues" and not being motivated to action, one who goes through Manic Depression also can be very high-energy and overly achieving - not being stabilized with a more constant emotional state.
Of course there are various medications on the market that can be beneficial to someone with this condition, though in my opinion I attempt to use and locate natural sources before placing artificial chemicals in my own body.
As with other types of Depression, a great way to stabilize the energetic body and create a more harmonic state within the mind/body connection and to keep from going to the emotional extremes is using Meditation and Yoga.
Both of these techniques have been around for thousands of years.
They have been proven and documented to be beneficial against many ailments, especially in regards to Mental health.
Meditation and Yoga are both designed to Calm the mind, release negative thoughts and feelings and begin to stabilize the chaotic inner states that are created by dealing with Manic Depression.
It may not happen overnight, but resolving Manic Depression is quite possible.
Continue on a path and put effort into a practice and see where it can take you!