How does inhaling glue affect a patient's brain?

Inhaling glue leads to the active chemicals it contains entering the lungs where they can be absorbed into the bloodstream. From there, these substances circulate throughout the body, including reaching the brain. This process highlights how inhalation of volatile substances can have systemic effects, particularly neurological, as these chemicals often affect neurotransmitter activity and brain function upon reaching their target.

In contrast, other methods of absorption described in the incorrect options do not apply to the typical route of exposure associated with inhaling glue. While the body can absorb some substances through the skin or mucous membranes, the primary and most dangerous exposure route for inhaled substances, especially solvents found in glues, is through the lungs and subsequent distribution via the bloodstream. This makes the choice regarding cross-absorption from the lungs into the bloodstream the most accurate and relevant in the context of the effects on the brain from inhaling glue.