Can Spironolactone for adult acne induce Restless Leg Syndrome and insomnia?

Don't worry, nothing is wrong with you!!  The first thing they teach us in pharmacology class in med school is "any medication is capable of causing any side effect"  You are just sensitive to it.  
Spironolactone is actually a diuretic that happens to be very effective for hormonal acne.  It acts at the kidney to cause more sodium to be released in the urine but to do this it has to "trade" a potassium ion for a sodium ion.  That causes you to urinate excess water as the water follows the sodium but it can cause the potassium levels to rise as well.  This electrolyte disturbance may be causing your insomnia and restless legs.  It may be worth trying lower doses and slowly titrating up to allow your body time to adjust, or having it compounded into a topical form.  Check with your prescribing doc about the best course of action but don't stress about your side effects.  They make sense as possible issues when you consider how spironolactone works.  
Hope this is helpful.  Best of luck to you,
Dr. Amy

Spironolactone is a great drug for hormonal acne, but it does have some side effects.  Excessive sleepiness, not insomnia is one of the potential reactions.  In addition, spironolactone can cause some muscle aches but restless leg is not listed as a potential side effect.  Hope this helps. Here is some info on hormonal acne.