Hi, The common side effects of gardenal include drowsiness, gait disturbances, dependence, cognitive dysfunctions, and respiratory depression. If you stop taking it suddenly it may cause tremors, anxiety, restlessness, vomiting, seizures, delirium, and cardiac arrest. Gynexin an over the counter herbal supplement claims to be effective for the treatment of gynecomastia however its efficacy and safety has not been scientifically proved. Gynecomastia usually subsides gradually and hence it does not require any treatment however if is troublesome consult your doctor for proper evaluation and also to determine if there is any underlying cause for it. Your doctor might advise you drugs like clomiphene or tamoxifen, if there is no response then its surgical removal is the most effective treatment. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Mohammed Taher Ali, General & Family Physician