[Cif]

IMHO, yes it is tamoxifen and the reason why I believe that is because I have increased cal burning activities and dropped cal intake and even tried fasting and gained 5-10 pounds a week on tamoxifen.

Before Tamox I could eat what I wanted (which my pref is fruit, veggie, lean protein) and could literally control my weight by food intake. Post Men, cal, exercise, fluid all being equal just add Tamoxifen and poof 5 pounds a week gain, now 10 pound gain in week three of Tamoxifen - and that is with cal dropped and added exercise of clearing 300 foot driveway of snow every few days (oh, Percocet has always been in play 1-2x week for myopathy/neuropathy pain breaks since April).

weight/treatment history (relearning reading and writing, spelling, and so much after chemo brain hit, so sorry this post bad):

102 pounds and chemo (TCH) started 1 mo after mast from dec-apr. Gained weight, expected (prohibited from eating fresh fruit and veggies per Dr to decrease infection risks - ate carbs first time in years, broke 10 years no pasta - was yummy)

122 - 110 feb- june Herceptin continues @21 days till dec
Got serious limb and brain issues after chemo's 4-6, if sit still pain issues got worse, used pain killers and cleaned house all day since it takes me days to complete a task that normally took 30 minutes before chemo.

102 pounds sept - dec 1 (dec 1 last infusion - yay)
Dec-Jan 102 pounds and in control of my weight including added silicon.

Jan started Tamoxifen and gaining 5 pounds a week first two weeks all else being the same.
Jan third week gained 10 pounds that week, only drank green tea, leek and cabbage soup made from scratch with slice of turkey - throwing out my normal super low carb high veggie and fruit diet to yet lower but not to point body will auto store when sensing intake too low.

115 - all in mid section, a place that was always an hour glass even when heavy. Looks like fluid retention - if true - then I'm going to drown ha ha.

The big problem is while researching how to resolve this I hit professional doctor articles about how Tamox increases hormone neg cancers by 100x's% vs the few % it decreases hormone pos.

Going to change years of exercise from mostly aerobic/anaerobic to weight bearing to see if that will fix.

Also read about introducing Metformin to control weight gain while it may also reduce cancer risks, but my research on scale 1-10 on that is .0001

Update March 27 2015

NO CARBS and limit fluid intake including water (not recommended) equals weight maintained. Add four hours (yep, it takes a lot with tamox) over the day of Kinect Adventures and lost 10 pounds and replaced couple of meals with Naturade's pea protein. Still unable to get access to metformin, GP will 'think' about it, Ono doesn't return calls unless fever or bleeding so that was dead end. Why I know it is Tamox and NOT meno, because Ono left me a couple months to recoup somewhat from very bad chemo results (falling down, memory, speech, losing time, lost in own house) before intro of tamoxifen, and with meno for a year no weight issues and ate normal and more without issue. Intro tamox and poof, serious weight and water weight issues and even men's extra large socks are tight and I'm a slender less than 5' pixy.

Choice is less food, water, and nutrition risks, or scoring metformin.