Hi! I'll be glad to be of help with this issue.
I can imagine how worrisome and distressing this situation must be for you. You are clearly a loving and caring parent and seeing your son go through this distress is very difficult. That it is leading to self worth issues is common to almost all children who have stuttering issues. Children as a whole have difficulty with those who are different in almost any way. And stuttering singles out a child among his peers.
Stuttering is more common in boys as well. There are two common causes for stuttering: developmental/genetic and emotional. Differentiating between these two general causal areas will need to be done by professionals. Getting professional help, then, for your son while he's still young can help him feel better about himself and to even perhaps control the stuttering for the rest of his life.
The first stop should be to his doctor. Your doctor will then give you a referral to a speech/language pathologist. This is the most common professional referral for diagnosis and possible treatment.
The doctor and/or speech pathologist may also recommend a psychologist who specializes in Cognitive Behavioral Therapy (CBT) to work with your son. You should feel free to discuss such a referral also. This can be extremely helpful not only for working on the stuttering itself but also for the self worth issues you've already seen are present. The psychologist can also help you and the rest of the family with tools for helping your son, which can be so useful. So if the doctor or speech pathologist do not bring this up, please consider doing so and adding this professional to your son's team.
There are no medications for stuttering. So given that pharmacological treatment is not an option, try to gather the full spectrum of professionals I've discussed above. In the case of stuttering, the more help he can get, the better the outcome will be. So don't be shy in asking for help.
Okay, I wish you the very best!
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