My son has been on Zoloft for a few years. This is his 4th year on it. He has increased dosage each year. He is now on 50 mg and is 12.5 years old. He has been doing well with Zoloft and we see good results in him. My question is: he still has "social anxiety" and the feelings of "I don't care" ... Although we see improvement, he still demonstrates these challenges. Would it help if he increased to 75 mg? Thank you so much.