A Marijuana Tincture is way of consuming medical marijuana through alcohol extraction. Marijuana Tinctures are very concentrated, so a dose may be only a few drops or a teaspoon or two. For best results it is important to use pure alcohol like Everclear, which is 95%. Vodka is good, but when it says 40%, it means the rest is water. If you are wanting to use vodka, you should use THC induced Vodka which will add to the potency. In whole-plant cannabis, THC content is expressed as THCA (tetrahydrocannabolic acid) prior to decarboxilation into THC, which takes place when cannabis is heated during cooking, and smoked or vaporized ingestion. THCA is a mild analgesic and anti-inflammatory but does not have good affinity with our CB1 receptors, so in order to make a THC-rich tincture that has many of the same therapeutic effects as smoked ingestion (including rapid absorption, quick relief and ease of self-titration), we must convert the THCA in the plant matter into THC prior to extracting it through an alcohol soak.