I want to echo Mage on resisting medication. It is a mask, not a real treatment, and should be used only as a last resort, if your child is unable to cope. Most AS symptons can be controlled by correcting the environment the child faces, instead of trying to change the child. That is, by far, the preferred approach - to find the environmental triggers and mitigate them.
I personally do not see the speech issues you mention as something to medicate against, or that medication will be effective for. The common treatment for echolia, repitition and other speech issues is to work with a speech therapist.
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Mom to an amazing young adult AS son, plus an also amazing non-AS daughter. Most likely part of the "Broader Autism Phenotype" (some traits).