Weight Gain Due to Medication

I was doing really well; I had dropped 10 lbs last fall while training for a half marathon. I decided I felt good enough to train for a full (marathon), so I began that in February. Last November, I began taking a medication -- Spironolactone -- to help with symptoms from endometriosis. This is a hormonal drug (androgen blocker) and a potassium-sparing diuretic. It really helped with my symptoms and also cleared up my acne somewhat. Recently though, I have seen the pounds piling back on. I'm still marathon training, probably eating more because long runs make you hungry (but still logging), and I could not figure out why I was gaining. I didn't read anything about weight gain when I read about the drug initially.

After doing lots of digging, I found stories from women who had taken this med who reported weight gain that was incredibly stubborn to get back off. I guess it makes sense, this drug is sometimes prescribed to transgender men to make them appear more female. So what was this drug telling my 40-something year old body? Gain weight. I've stopped taking it.

The purpose of my post is to ask if anyone has experienced something similar with medication and if it took just a little more effort to get that kind of weight off. I'm not going to do anything different immediately, with my marathon being 19 days away. Afterward, I'm going to cut my calories way down and do more strength training/lifting.