I am taking cymbalta (duloxetine) for fibromyalgia and have gained 20lbs with hand and feet swelling. are there other drugs that treat fibromyalgia with less side ?

Possibly: All medication have side effects. There are a number of medication that are indicated for fibromyalgia. Lyrica, savella, (milnacipran) effexor, Pristiq and muscle relaxants have all been shown to be helpful for fibro. Regular, moderate, non-impact aerobic exercise and cognitive behavioral therapy have been shown to be as if not more effective than medication and have almost no adverse effects.

Hands/feet swelling: Weight gain is not a common side effect from duloxetine [cymbalta] treatment of fibromyalgia syndrome [fms]. The combination of weight gain with swelling of hands and feet suggests another condition [eg, kidney disease, heart disease etc] or another drug [steroidal, non-steroidal antiinflammatory, pregabalin, etc] used at the same time or even in the past. You should see your physician soon!

Make sure is Fibro: Fibromyalgia is one of the most overly diagnosed condition today. There are many underlying conditions that can explain many of the symptoms that are more common-place and actually treatable. Conditions of the neck and low back will frequently have "myofascial" (muscle, tendon, ligament=soft-tissues) related pain that will spread quite far at times. Seek pain specialist eval. If needed for options.