Dextroamphetamine is a stimulant, and stimulants are very effective in helping with depression, although not usually prescribed for that purpose due to the potential for abuse. In the U.S., these stimulants are on the controlled schedule list, which means extra precautions must be taken when prescribing (no more than a 30 day supply, must see the prescriber each time for a new RX, cannot have the RX phoned in to the pharmacy, RX expires 3 days after it is signed by the doc, etc.). Stimulants like dextroamphetamine work by increasing dopamine and norephinephrine in your system. These are both neurotransmitters, and more of each can help with depression. Some anti-depressants help by raising these NTs also. For example, the AD Bupropion (Wellbutrin) also increases the levels of these two NTs, by blocking reuptake of each from the synapse back into the releasing neuron. Dextroamphetamine also blocks reuptake of these NTs but also leads to increased release into the synapse, so you get a one-two punch with this drug, instead of the more limited "one" punch of a more conventional AD such as Bupropion. So bottom line, yes, this med can help with depression.
This medication should not be prescribed to anyone for any indication (including ADHD) if the person is known to have had drug addiction/abuse problems.
There are new formulations of the drug that are not prone to abuse (and resale) because of how they are formulated, for example, Vyvanse.
I have ADHD-like symptoms and my PNP originally prescribed me Bupropion because it can help with ADHD and also helps with depression, which she thought I also had some symptoms of. This helped somewhat. To get further relief from the ADHD symptoms, she added Vyvanse to that (a dextroamphetamine), and that really helped my ADHD-like symptoms as well as depressive symptoms. I decreased the Bupropion dose and am still taking some of that as well as the Vyvanse. PNP said I could give up the Bupropion if I wanted, as the Vyvanse is probably enough to handle both my ADHD and my depression. She said amphetamines are very effective at relieving depression symptoms.
I have been taking Vyvanse for about 6 months and have experienced no bad side effects, except the first few days, when I had some insomnia. I am not addicted nor have I developed tolerance (need more of the drug to achieve the same effect). Sometimes I don't take it if I don't feel I need it or if I forget to take it until too late in the day, then I just skip it (because it would keep me awake).
Vyvanse is ingested in a chemically inactive form and slowly metabolized to the active form. There is no "buzz" or "jolt" or "high" associated with taking it. It is very smooth, gradually increasing in one's body over the day and decreasing. One dose in the AM lasts me until bedtime. If I don't take it, I don't have any bad effects like shakes or headaches or cravings. I have no history of addiction or illicit drug use and have great respect for the power of pharmaceuticals. I would not take this drug unless I had researched it thoroughly.
I really appreciate that my PNP didn't try to prescribe me an SSRI like so many doctors. I don't appear to have a lack of serotonin and so have no need for ADs like Prozac, Lexapro, Paxil, etc. I seem to do well with more dopamine in my system.
If you have tried many meds with no success (treatment resistant depression), then I think giving a stimulant a try is worth it, unless you are addiction-prone or have some other medical problem that isn't compatible with stimulant use (such as heart trouble).
I would not be scared of this. It could really help. If it doesn't, then you can just stop taking it. Keep in close touch with your doc when first starting it, just to make sure you are doing OK. It does not generally cause weight gain, but can lower appetite in some people and lead to weight loss. If you are already underweight, keep a watchful eye if you start this med.
BTW, I am also in psychotherapy, and this is helpful with depression too.
Good luck!
Vyvanse:
http://en.wikipedia.org/wiki/Vyvanse