Brief Answer:
consult a pediatrician or neurologist too

Detailed Answer:
Hello dear,
I have gone through your question and understand your concerns.
In child with ADHD usually diagnosis is made on evaluation by child psychiatrist and defined criteria.
The most common symptoms are impulsivity, inattention, poor school performance , interrupting task in between.
Speech delay as compared to normal child is present. The child has impulsivity with inability to control himself from talking doing some act and staying at one place.
Some language abnormalities may also be present.
But if no word is being uttered for 6 years of age in your case then you should consult a speech therapist and pediatrician/ Neurologist for evaluation.
Hope you found the answer helpful.
Do get back to me for further queries.
Regards
Dr Neeraj Kumar
Neurologist

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