Hi.. Thanks for the query.. Lip twitching or quiver can occur due to a side effect of medication or sudden changes in blood pressure levels with the medicine.. Other causes that can also commonly cause quiver of lips are Vitamin B12 and calcium deficiency, potassium deficiency, traumatic injury or inflammation of facial nerve that supplies muscles of face,anxiety and panic attacks, nerve inflammation and infection caused by viruses etc.. I would suggest you to first of all consult your treating Physician and get evaluated and a thorough clinical evaluation can help in diagnosis.. In case if it is a side effect of medicine then it has to be changed.. In case if medicine is not the cause then you will be advised to get investigations done like MRI, CT Scan, Nerve conduction studies, Electromyogram etc to rule out the exact cause of the problem and treat you accordingly.. You can be advised to take multivitamins along with calcium and potassium supplements.. You can do warm compresses over the lips. You can also do breathing exercises along with meditation to keep stress minimal.. Hope this helps.. Regards.