Vaporizadores => Área Médica - Uso terapéutico => Estudios e investigaciones => Mensaje iniciado por: 9delta en 08 Noviembre, 2011, 19:34:16

Título: Cannabis Vaporization Offers Advantages Over Orally Administered THC
Publicado por: 9delta en 08 Noviembre, 2011, 19:34:16
Os dejo un extracto del documento de NORML: Marinol vs. Natural Cannabis (

Cannabis Vaporization Offers Advantages Over Orally Administered THC

Vaporization is an alternative method of cannabis administration that holds distinct advantages over both smoking and oral administration. Cannabis vaporization suppresses respiratory toxins by heating cannabis to a temperature where cannabinoid vapors form (typically around 180-190 degrees Celsius), but below the point of combustion where noxious smoke and associated toxins (i.e., carcinogenic hydrocarbons) are produced (near 230 degrees Celsius).40 ( Although a comprehensive review of cannabis and health conducted by the National Academy of Sciences Institute of Medicine found "no conclusive evidence that marijuana causes cancer in humans, including cancers usually related to tobacco use,"41 ( studies have found that heavy cannabis smokers face a higher risk of contracting bronchitis and respiratory illnesses.42 ( This risk is likely not due to the inhalation of cannabinoids, but rather to the exposure of noxious smoke. Because vaporization can deliver therapeutic doses of cannabinoids while reducing the users intake of pyrolytic smoke compounds, it is considered to be a preferred and likely safer method of cannabis administration than smoking.43 (
In practice, cannabis vaporization offers considerable advantages over oral THC consumption. While the oral ingestion of Marinol avoids the potential risks of smoking, it has significant drawbacks. Because of synthetic THC's poor bioavailability, only 5-20 percent of an oral dose ever reaches the bloodstream44 ( and the drug may not achieve peak effect until four hours after dosing.45 ( Moreover, because Marinol is metabolized slowly, its therapeutic and psychoactive effects may be unpredictable and vary considerably, both from one person to another, and in the same person from one episode of use to another.46 ( By contrast, cannabis vaporization delivers cannabinoids to the bloodstream almost instantaneously.47 ( Vaporization's rapid onset also allows patients to self regulate their dosage of cannabinoids by immediately ceasing inhalation when/if their psychoactive effects become unpleasant.48 ( After oral administration of Marinol, patients have no choice but to experience the full psychoactive effects of the dose consumed. These dysphoric effects may last several hours.
Because of its rapid onset, vaporized cannabis is more desirable than Marinol for patients requiring a fast-acting therapeutic agent, such as those combating oncoming attacks of nausea, seizures or muscle spasms. Cannabis vaporization also offers a unique advantage to patients suffering from nausea and vomiting because it allows them an alternative delivery route to swallowing. Cancer and HIV/AIDS patients often report that their stomachs cannot hold down Marinol capsules during bouts of severe nausea49 ( and many rely on natural cannabis and cannabinoids for symptom control.50 ( In a 1994 survey of oncologists, respondents ranked synthetic THC ninth on a list of available antiemetic medications.51 ( In another survey of oncologists, 44 percent of respondents said that they believed natural cannabis to be more efficacious than oral synthetic THC; only 13 percent of respondents rated Marinol more effective.52 ( A 1997 survey of physicians found that a majority preferred megestrol acetate over Marinol as an appetite stimulant in patients with HIV/AIDS.53 (
As a result of Marinol's slow onset and poor bioavailablity, scientists are now in the process of developing a new formulation of pulmonary dronabinol, delivered with a pressurized metered dose inhaler.54 ( In a Phase I study, pulmonary Marinol delivered via an inhaler provided rapid systemic absorption. Unlike oral synthetic THC, it's possible that pulmonary Marinol "could offer an alternative for patients when a fast onset of action is desirable."55 ( However, FDA approval of pulmonary Marinol and/or its inhaler remains years away. Sativex, an oral cannabis spray consisting of natural cannabinoid extracts, has greater bioavailability and is faster acting than oral synthetic THC. Clinical trials comparing its bioavailability and time of peak onset compared to vaporized cannabis have not been performed, though anecdotal reports indicate that vaporized cannabis and its cannabinoids likely possess greater bioavailability and are faster acting than the Sativex spray.

Fuente: (