Inhalation
The onset of cocaines euphoric effects is fastest with inhalation, beginning after 3–5 seconds. However, inhalation gives the shortest duration of euphoria (5–15 minutes). Cocaine is smoked by inhaling the vapor produced when free base cocaine is heated to the point of sublimation. In a 2000 Brookhaven National Laboratory medical department study, based on self-reports of 32 people who used cocaine who participated in the study, "peak high" was found at a mean of 1.4min +/- 0.5 minutes. Pyrolysis products of cocaine that occur only when heated/smoked have been shown to change the effect profile, i.e. anhydroecgonine methyl ester, when co-administered with cocaine, increases the dopamine in CPu and NAc brain regions, and has M1- and M3- receptor affinity.Smoking freebase cocaine is often accomplished using a pipe made from a small glass tube, often taken from "love roses", small glass tubes with a paper rose that are promoted as romantic gifts. These are sometimes called "stems", "horns", "blasters" and "straight shooters". A small piece of clean heavy copper or occasionally stainless steel scouring pad – often called a "brillo" (actual Brillo Pads contain soap, and are not used) or "chore" (named for Chore Boy brand copper scouring pads) – serves as a reduction base and flow modulator in which the "rock" can be melted and boiled to vapor. Crack is smoked by placing it at the end of the pipe; a flame held close to it produces vapor, which is then inhaled by the smoker.
Dissections within the carotid arteries or vertebral arteries may compromise blood flow to the brain due to thrombosis, and dissections increase the risk of vessel rupture. Idiopathic
Idiopathic diseases are those that occur spontaneously without a known cause. Moyamoya is an example of an idiopathic cerebrovascular disorder that results in narrowing and occlusion of intracranial blood vessels. The most common presentation is stroke or transient ischemic attack, but cognitive decline within children may also be a presenting symptom. The disease may begin to show symptoms beginning in adolescence, but some may not have symptoms until adulthood. Pathophysiology
Mechanism of brain cell death
When a reduction in blood flow lasting seconds occurs, the brain tissue suffers ischemia, or inadequate blood supply. If the interruption of blood flow is not restored in minutes, the tissue suffers infarction followed by tissue death. When the low cerebral blood flow persists for a longer duration, this may develop into an infarction in the border zones (areas of poor blood flow between the major cerebral artery distributions). In more severe instances, global hypoxia-ischemia causes widespread brain injury leading to a severe cognitive sequelae called hypoxic-ischemic encephalopathy.An ischemic cascade occurs where an energetic molecular problem arises due to lack of oxygen and nutrients. The cascade results in decreased production of adenosine triphosphate (ATP), which is a high-energy molecule needed for cells in the brain to function. Consumption of ATP continues in spite of insufficient production, this causes total levels of ATP to decrease and lactate acidosis to become established (ionic homeostasis in neurons is lost).