"i began phentermine on 5-5-15.as of today 5-19-15 i have lost 16 pounds.i take the 37.5mg dosage.the first 2 nights i had insomnia but that was it.i also do have a dry mouth.that just makes me drink more water which is a good thing.i have energy to be more active.i walk 3 miles 5 days a week and also follow a 1200 calorie low carb paleo eating plan."