hello distressed 24year old, thanks for writing to HCM. I read your query and understand your concern whether taking Drotin tablet is ok? Coming to the query,you have mentioned excessive unbearable pain during periods which is called dysmenorrhea and yes drotin which contains drotaverine which is an antispasmodic and smooth muscle relaxant is used prevalently in your query you said one tablet per month which i assure you is a very safe dosage and wont cause any side effect. commonest dosage is 120-240mg per day in 3 divided dosages. common side effects are nausea,giddiness,hypotension etc which are not worrisome If you are overusing the drug then only you need to worry about the load given on liver and kidney to remove it from the system.Since you are using only one tablet/month ,there is no worries alternatively you can try,ibuprofen twice to thrice daily for 3 days of the period when its painful(use if you dont have gastritis/stomach ulcer) and also keep a low sodium diet and try hot warm compresses over the abdomen when pain intensifies hope i have clarified in detail and hope it helps. take care and good day.