I agree- my endoc said never take generic thyroid medicine.
Ask the Dr to change him back to Synthroid...some people do better on synthroid than levothyroxine and vice versa. Stay away from the generic medicines. Did the dr run thyroid panel before changing dosage? It takes at least 6 weeks for med to level out, and thyroid labs should be done every 6 weeks until optimum levels are reached and held. Hashimoto's can be a rough ride for some.