I am 29 years old and suffering from endometriosis. I am receiving Depo-Lupron shots for six months. I am on my fourth shot. My doctor did not advise me of any major side effects, but I feel very weak and sometimes I feel I might pass out. I am unable to work. Can you please tell me more about this medicine?

D.C.

GnRH-agonist medications Lupron and Zoladex work by suppressing estrogen production, so it is likely that any of the side effects you experience while taking Lupron are due to low estrogen levels. Low estrogen levels can result in hot flashes, headaches, mood swings, weight gain, muscle and bone pain, sleep disorder, bone calcium loss and memory difficulties.

These problems can all be solved by combining the use of GnRH-agonists with a combination of low-dose estrogen and progesterone. This approach is called add-back therapy. Add-back therapy usually prevents all the side effects mentioned above, while not diminishing the treatment's effectiveness at alleviating endometriosis symptoms.

Depo-Lupron is approved for six months of use. Unfortunately, once the medication is stopped at the end of six months, symptoms recur rapidly. An additional benefit of add-back therapy is that it enables safe use of these medications for longer periods than six months. In fact, many women have been safely treated this way for many years with long-term relief of symptoms.

Your symptoms may also not be related to GnRH-agonist therapy, and add-back therapy may not appropriate for you. I would recommend you discuss your symptoms and all appropriate options with your physician, who best understands your particular situation.