Vaporizers do not completely eliminate respiratory irritation. Vaporized cannabis sativa (marijuana) or tobacco, if inhaled in large enough quantities, can frequently induce severe coughing. Vaporization systems are usually devised using a water and/or ice-cooling system that uses water vapor or clouded moisture to attach to the E-cigarette or intended inhalation material. Weighed by the moisture, the vaporized particulate matter attaches to fixed objects on the inside of breathing passages. From there, the bloodstream absorbs the chemical, which releases its intended effect. Some vaporizers use a water pipe or a "vaporization water tool" with ice in an attempt to reduce the vaporization temperature and to deliver the fluidized particulate matter in larger inhalations. The user can inhale more at a time without suffering respiratory irritation by breathing through the tube cooling the dry vapor.
There are three types of vaporizers. The direct heating vaporizer is a heated vaporizer. Material, such as cannabis sativa (marijuana) or tobacco is burned on the heating element or hot plate, which incinerates into particulate matter or vaporizes into gaseous form. The user then inhales the particulate matter or gas as it is suspended inside the glass-enclosed, heated chamber. The indirect heating vaporizer is also heated, but instead the material is packed inside a tubular glass chamber rather than placed on a heating plate inside a glass chamber. Once inside a tubular glass chamber, the packed material is heated at a lower temperature allowing the particulates or gases to release for inhalation through the opposite side of the tube. This reduces the intensity of gases and carbon monoxide released during the vaporization process. Heat gun vaporizers use a flask-type glass with a side port or opening for the heat gun to inject heat. The heat and material combine in the side port and the vaporized particulates and gases release up through the top of the flask. For those who are connoisseurs of cannabis (marijuana) the temperature that yields the most aromatization without complete incineration is to vaporize sativa at approximately 240°C/464°F.
The principle of the vaporizer is one of gas-solid transport using a pneumatic conveyance. The transport of solid particles with air as the conduit is called pneumatic transport. When fluid is introduced, such as water or ice, fluidization occurs trapping the atomized particulates. With pneumatic transport in force, gravitational and atmospheric friction forces are overcome thus propelling the fluidized particulates to the intended user. Prevention of mechanical plugging or clogging of the vaporizer and communicating lines is important, especially when large quantities of atomized material must be conveyed to the user. To accomplish this, the diameter size of the vaporizer and communicating lines must be at least three to five times the maximum particle dimension. Moreover, the density of the material vaporized will affect the minimum transport velocity and lower the pressure within the lines in direct proportion to inhaled velocity.
The breathing system of the human body can be divided into roughly two tracts: Upper and Lower Respiratory Tracts. While the Lower Respiratory Tract is entirely the lobes of the lungs, the remaining parts, such as the bronchial tubes or branches to the lungs, trachea or main breathing tube, larynx or voice box, pharynx or throat, nose, sinuses, and mouth all comprise the Upper Respiratory Tract. The lining of the trachea or breathing tube is built with goblet cells that extrude antibodies, neutrophils, lymphocytes, and other acute phase reactants to bathe the throat. The base of the breathing tube where the two, main-stem bronchial tubes separate towards the lungs has a sensory patch called the carina, which triggers the cough reflex should heavy phlegm or dangerous dust or heat enter. Since the bronchial tubes are merely extensions of the trachea, or breathing tube, they have the very same structures and behave the same with immune responses. Some airborne particles exceed 0.5 microns or 0.0005 millimeters. These are sensed by the bronchial tubes and trapped along the lining. Those particles that are smaller than 0.5 microns are undetected and proceed into the lungs. Tobacco and cannabis sativa (marijuana) are smaller than 0.5 microns and understandably pass directly to the lung tissue.
The biomechanics of cannabis sativa (marijuana) is unlike that of tobacco. The active ingredients of cannabis sativa include delta-9-tetrahydrocannabinol and cannabidiol among other derivatives, which are all collectively termed "cannabinoids." From multiple studies conducted by the United States Institute of Medicine, limiting the research to unpurified cannabis sativa leaves, the Institute discovered some unique human biomechanics associated with this substance when it reaches the bloodstream. First, cannabinoids were found to have an apparent, natural role in pain modulation or reduction, reduction in motor or muscle movement control, and memory. Second, there was found an apparent natural role in the immune system, which uses a multi-pronged approach and therefore the mechanisms are not clear because the receptors that cannabinoids use are different from normal physiology.
It is quite clear that the human body quickly develops a tolerance to cannabinoids, which leads to dependence. This is not dissimilar to the tolerance and dependence characteristics seen in benzodiazepines such as diazepam (Valium), opiates such as morphine and Oxycontin, cocaine products and nicotine. For this reason, there are withdrawal symptoms, but the withdrawal from cannabinoids is not as severe as the other agents cited. Nonetheless, a distinctive marijuana withdrawal syndrome has been identified and includes restlessness, irritability, mild agitation, insomnia, sleep disturbance, nausea, and cramping.
The fact that cannabinoids employ different receptors within the human body leaves the invitation open to future consideration for limited medical use. Such licensed medical use could be for terminal cancer and terminal Human Immunodeficiency Virus patients who have debilitating symptoms (such as intractable pain or vomiting). In these cases, the benefits may outweigh the risks of short and long term damage to memory and motor nerve and muscle function.
Cannabis sativa is freely marketed in some countries such as Canada in an oromucosal or breath atomizer spray. One marketed brand is Marinol by Solvay Pharmaceuticals, which is dronabinol a synthetic delta-9-tetrahydrocannabinol. Cesamet marketed by Valeant Pharmaceuticals International is nabilone, a synthetic derivative of delta-9-tetrahydrocannabinol. Although other countries have different licensing privileges, Canada authorizes dronabinol and nabilone to be used for chemotherapy-induced nausea and vomiting while dronabinol is further approved for HIV-associated anorexia or inability to eat. Meanwhile, the oromucosal or breath atomizer spray mixture of delta-9-tetrahydrocannabinol and cannabidiol is conditionally approved for the neuropathic pain common in multiple sclerosis and pain associated with cancer.
In fact, in one study it was determined that regardless of the administration of cannabinoids (oral medication or smoked cannabis sativa), short-term use does not raise viral load in individuals with HIV infection when they are receiving routine regimens of their antiretroviral therapy; specifically, those containing nelfinavir or indinavir. Nabilone appears to be a beneficial, well-tolerated treatment option for fibromyalgia patients based upon clinical practice where significant improvement has been noted in pain relief and functional improvement. While there was no effect on morning stiffness, cannabis was found to have a statistically significant reduction in pain for rheumatoid arthritis in a 75 patient study. Moreover, in 30 research studies cannabinoids were found superior to the accepted antiemetics (anti-nausea) medications prochlorperazine, metoclopramide, chlorpromazine, thiethylperazine, haloperidol, domperidone, or alizapride, which are essentially low-dose anti-psychotics.
It is estimated that 10%-20% of patients with multiple sclerosis, chronic pain, HIV/AIDS and epilepsy admit smoking cannabis for therapeutic purposes. Indeed, in one study, smoked cannabis sativa reduced daily pain by 34%, considered significant by statistics. Also, a greater than 30% reduction in pain was reported by over half the cannabis group in contrast to less than a quarter of the control group that was not receiving any cannabis. Still, many, when researched were found to be at increased risk for psychotic outcome. Indeed, it is considered not an uncommon finding in psychiatric inpatient wards to see young people, aged 17-25 who trigger schizophrenia after using cannabis sativa.
The chronic effects of cannabis sativa (marijuana) include all the same risks of tobacco. Tobacco induces emphysema or a rupturing of the alveoli, the grapelike oxygen-exchanging functional units of the lungs and chronic bronchitis or scarred thickening of the bronchial system to prevent exhalation permanently. Additionally, when cannabis sativa was researched in 23 randomized controlled trials using short-term, medical cannabinoids there appeared to be an increased risk of adverse events. These adverse events were later determined non-serious.
Unfortunately, there is a narrow therapeutic window of dosing for cannabinoids. In three research studies, it was found that slightly lowering the synthetic dose made cannabis no more effective than placebo or sugar pills. Conversely, raising the dose slightly above the therapeutic range created reversal of pain relief and instead worsened pain. Moreover, the risks associated with long-term use were not clearly documented in the 23 clinical trials and observational studies. To more clearly isolate the clear dangers of medical cannabinoid use, future research must be more rigorous and of higher-quality.
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