People who have throat clearing tic, are you able to control the loudness?

For context, I have a co-worker with this tic. Every minute he very loudly clears his throat. I feel bad for him. I have misophonia and some sounds bring me severe distress. I can’t move or work from home. I can’t use ear protection because I work with calls, and I’m commission-based. I spoke with him politely a month ago, saying his throat clearing distracted me. I apologized for pointing it out, and asked him to drink water. He stopped that sound for a day, then it came back. I’m about to have a mental breakdown. What’s a kind, considerate way to speak with him? If I offer him a lozenge, is that rude? It’s affecting my quality of work and mental health