Indica vs. Sativa
All cannabis products, including medical marijuana, come from two species of plant: cannabis sativa or cannabis indica. Although they are closely related, these plants have different characteristics in the kinds of medicines each can become. On top of this, there a huge amount of variation in size, shape, and chemical content within both species. This comes from growers selectively breeding for certain traits, creating different strains of cannabis. Think of it as the kind of breeding that led to so many breeds of dog with different personalities, sizes, and colorations, even though they are all the same species. The marijuana plants can be crossed to make hybrids. You can find a quick overview of the plants here.
It isn’t all about appearances
Cannabis indica (or simply “indica”) grows shorter and stouter than sativa plants, with shorter and broader leaves. When used recreationally, many people report that they feel more of a calm, “stoned” feeling, and much less of a high. This is because the chemicals that give marijuana plants their effect come in different amounts, depending on the plant strain. The major chemicals are THC and CBD (click here for more on these and other compounds found in marijuana), and as a rule, indica has more CBD than THC. The relaxing effect of its recreational use can be refined as the plant is turned into your medication. For example, medical marijuana products made from indica are most of what you can use for insomnia, anxiety, and some kinds of pain.
Cannabis sativa (or just “sativa”) tends to grow much taller than indica, with narrow, pointed leaves. This is the species that, when used recreationally, gives users the “high” of creativity, plenty of energy, and a general feeling of hyper-awareness. Sativa will usually have more THC that CBD, and it is the THC that stimulates the user. The stimulatory effect of THC is concentrated into the stabilizing effect for patients with mood swings, or that suppressed the nausea of patients undergoing chemotherapy. You can click here for more information on the comparison of these species.
Keep in mind that there is a lot of variation within the two species, and the differences in CBD and THC levels is what sets if the plant is used for different medical conditions. For the patient, the most important thing to know about sativa versus indica is that it is not important. These labels are used to categorize plants based on how they grow and look, which usually tells you if it has more CBD or more THC. For example, some indica strains have equal amounts of CBD and THC, while others can have twenty times the amount of CBD. Plus, if you remember that some cultivators create hybrids, then it can be frustrating to keep track of what plant source is the most appropriate for your medical condition. The key is to ask about the ratio of CBD to THC in the plant strain used for your medication, which you can learn more about by asking your physician.