I have read your query.
To answer your query straight - No, you cannot lessen the dose of Belviq. And, if you do so, it can become less effective or completely ineffective.
If you have started the course recently, I suggest you to continue with the prescribed dose for 12 weeks. If the desired result is not seen, then you can stop the medicine in consultation with your doctor.
is the common side effect of Belviq. Please wait for it to subside by itself. It should be gone by a week's time of starting the treatment. Meanwhile, drink plenty of fluids orally with lots of fruit juices.
Let me know if you have more queries. Wish you good health.