My Husband Has Been Taking 3-4 Percocet A Day(usually 3

My husband has been taking 3-4 percocet a day(usually 3 and never more then 4) for about a year now and he went one day without taking any and he felt hot/sick to his stomach/shaky and felt like crap and a friend gave him a clonozapam and that took the shakes away and helped him sleep and feel better.Is this a sign of addiction and if yes should he ween himself off them? He is worried he may be addicted and has never been addicted to anything before.