These harmful chemicals can be inhaled (in the case of air fresheners) or applied (in the case of perfumes). The substances diffuse into the brain rapidly, as they are lipophilic and readily transported across the blood–brain barrier. This is a result of increased membrane solubility and local blood flow, with central nervous system (CNS) solvent uptake being further increased with high levels of physical activity. When they are not detoxified immediately, the symptoms of toxic encephalopathy begin to emerge. However, in chronic situations, these effects may not become severe enough to be noticed until much later. Increased exposure time and increased concentration of the chemicals will worsen the effects of toxic encephalopathy, due to the associated structural CNS damage and direct functional impairment consequences.Subacute toxic encephalopathies are challenging to identify due to their often insidious tempo of evolution, nonspecific manifestations, relative infrequency as individual entities, and frequent lack of specific diagnostic testing. Yet they are crucial to recognize in aggregate, subacute toxic encephalopathies are a common problem that can lead to severe, irreversible harm if not diagnosed and treated efficiently. This article reviews the clinically relevant aspects of some of the more important subacute toxic encephalopathy syndromes caused by inorganic toxins, carbon monoxide (CO), anti- biotics, antineoplastic agents, and psychiatric medications.All therapeutic interventions are double-edged swords with benefits and adverse effects, and pharmacotherapy is not an exception.
Nevus comedonicus (also known as a comedo nevus) is characterized by closely arranged, grouped, often linear, slightly elevated papules that have at their center keratinous plugs resembling comedones. : 634 : 774

See also
Nevus comedonicus syndrome
Skin lesion
List of cutaneous conditions


== References ==