Commenting on the situation, Kildare North TD Reada Cronin said it is "an unbelievable but common enough situation".
The Taoiseach has admitted that more work is needed for individuals who have a dual diagnosis.
The admission came following reports that a teenager in Kildare can not be treated due to having both autism and a mental health diagnosis.
Commenting on the situation, Kildare North TD Réada Cronin said it is "an unbelievable but common enough situation".
She said: "Mental health services say they cannot treat him because of his ASD diagnosis, and autism services say they cannot treat him because of his mental health diagnosis."
She said after a recent suicide attempt and a 999 call, the 19-year-old, referred to as Seán, spent a night in the Lakeview unit attached to Naas General Hospital.
"Seán is not a diagnosis or a list of symptoms - he is a citizen of this State. There is no rest and no sleep for his family. His mother is out driving the back roads of Kildare, trying not to hit another deer and trying to keep Sean calm. I have been in contact with the HSE since last October about Seán to no avail," Deputy Cronin said.
In response to her queries, Taoiseach Simon Harris said Deputy Cronin "is right that people are not just a diagnosis or a number of diagnoses - they are people".
He explained how a "brief discussion" at the Cabinet committee on disability last week touched on the issue of dual diagnosis and that he will be "following up on that".
He added that he would be eager to use his offices to assist in the case of Seán.
More to follow.

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