Autism Pill?

Given the interconnected roles of glutamine, vitamin D, and serotonin, a simple solution could be a properly formulated pill.

Glutamate overproduction causes leaky gut, and glutamine closes up the pores in the gut, helping alleviate leaky gut. Leaky gut causes reduced vitamin D absorption. And as noted here,

vitamin D hormone activates the gene that makes the enzyme tryptophan hydroxylase 2 (TPH2), that converts the essential amino acid tryptophan, to serotonin in the brain. This suggests that adequate levels of vitamin D may be required to produce serotonin in the brain where it shapes the structure and wiring of the brain, acts as a neurotransmitter, and affects social behavior. They also found evidence that the gene that makes the enzyme tryptophan hydroxylase 1 (TPH1) is inhibited by vitamin D hormone, which subsequently halts the production of serotonin in the gut and other tissues, where when found in excess it promotes inflammation.

This mechanism explains many of the known, but previously not understood, facts about autism including: 1) the "serotonin anomaly" low levels of serotonin in the brain and high levels in the blood of autistic children; 2) the preponderance of male over female autistic children: estrogen, a similar steroid hormone, can also boost the brain levels of serotonin in girls; 3) the presence of autoimmune antibodies to the fetal brain in the mothers of autistic children: vitamin D regulates the production of regulatory T-cells via repression of TPH1. The Patrick/Ames mechanism is relevant to the prevention of autism, and likely its treatment.

 The authors say that

The study suggests dietary intervention with vitamin D, tryptophan and omega 3 fatty acids would boost brain serotonin concentrations and help prevent and possibly ameliorate some of the symptoms associated with ASD without side effects.

I would argue that this should be combined with glutamine as well.

Is it possible to have a treatment for at least some forms of autism in pill form? Very possibly.

A pill that combined glutamine, vitamin D, tryptophan, and omega 3 fatty acids could very well alleviate gut problems and improve cognition in many with autism.