Medical cannabis strains at a glance

Cannabis flower

cannabis flower

The use of cannabis as medicine goes back many thousands of years in history. In the course of the 18th century, the classification of plants into two or three cannabis varieties became established: Cannabis Indica and Sativa, sometimes also Ruderalis (as a commercial cannabis variety). These terms have become established, especially among recreational users, even if scientists today recommend a different classification. Why does medicine no longer consider the classification into cannabis indica, cannabis sativa and hybrids to be up-to-date? The categorization does not do justice to the differences in the mode of action. Rather, it seems useful to use the CBD or THC content and the terpene profile of cannabis flowers as a guide1.

Which cannabis varieties are there?

Cannabis belongs to the Cannabaceae (hemp family). In the ongoing debate about whether Cannabis is represented by one or more species, Cannabis is predominantly considered monospecific: Cannabis sativa L., which includes subspecies sativa, indica, or ruderalis, among others2. Incidentally, the "L" at the end refers to Carl von Linné, who gave the name in the 18th century. Most varieties of Cannabis sativa L. grown today are often referred to as "hybrids" because they are crosses of these historical subspecies. Yet the plant structure thus designated gives no indication of the cannabinoid content or composition of the plant3.

Generally, sativa strains are said to have an energizing and activating effect, while indicas are said to be relaxing, calming, and pain-relieving4. However, experts counter that the classification only makes sense in terms of appearance and growing conditions. The following differences become apparent:

Sativa varieties:

  • Well suited for outdoor cultivation due to their long flowering period.
  • Grow up to three meters high, even five meters possible outdoors.
  • Typical are rather long and thin leaves, outdoors also bushy growth possible
  • Origin: Mexico, Colombia, Thailand, Jamaica, ...

Indica varieties:

  • Short flowering time, therefore more used for indoor growing.
  • Bushy and short-grown plants.
  • Dark green and thick leaves.
  • High yield with heavy buds
  • Origin: India, Afghanistan, Morocco, ...

Neurologist and cannabis expert Ethan Russo offered the following assessment in an interview regarding the debate over indica and sativa classifications:

"There are biochemically distinct cannabis strains, but the distinction between sativa and indica, as often used in lay literature, is utter nonsense and a prime example of futility. One cannot currently estimate in any way the biochemical content of a particular cannabis plant based on its height, branching, or leaf morphology. The level of cross/hybridization is such that only a biochemical test can tell a potential consumer or scientist what is really in the plant. It is important that future commerce provide complete and accurate cannabinoid and terpenoid profiles."1

Cannabis strains in the 21st century

Molecular biology has clearly worked out that the binary classification of the cannabis plant into indica and sativa is incorrect when the plant is broken down to the molecular level. Molecular testing made it clear that while the two strains, sativa and indica, may differ in their growth patterns, they are the same at the molecular level. Therefore, research teams concluded: there is only one species of cannabis: Cannabis sativa L.1,3.

There are more than 700 varieties of cannabis for medicinal and recreational use. Many have dazzling names. Some of these varieties are direct subspecies of sativa, indica, and ruderalis, but most are hybrids. Some of the varieties are named for their smell, some for their parentage. There are no real rules for naming cannabis varieties.

If the term "Kush" appears in the name, it usually indicates an indica parentage, but often also refers to hybrids. Afghan Kush, Hindu Kush, Green Kush and Purple Kush are all varieties with an indica origin. Blueberry Kush and Golden Jamaican Kush, on the other hand, are hybrids. Similar mixing occurs with strains that have "Diesel" or "Haze" in their names: some strains are pure sativa, while others are hybrids5.

Relevance of cannabinoids and terpenes

Instead of dividing plants and their effects into sativas and indicas, most scientists today agree that the interaction of cannabinoids and terpenes (essential oils that give plants their smell) is largely responsible for the different effects of cannabis5,6 - in addition, the dose as well as the dosage form also play an important role7.

The best known cannabinoids of the cannabis plant are THC (tetrahydrocannabinol) and CBD (cannabidiol). The active ingredients are found in the female cannabis flowers and can cause different effects depending on the dose: The intoxicating THC can relieve chronic pain as well as nausea and vomiting, and researchers also observe an appetite-stimulating effect. CBD can have an anti-inflammatory effect and is also used to treat epileptic disorders6.

In order to achieve certain effects, researchers are constantly working on creating new varieties through crossbreeding. In particular, much research is being done on THC content: between 2000 and 2004, the average THC content of cannabis plants from the Netherlands increased from 8% to 20%8.

The entourage effect

However, the full spectrum of effects can probably only unfold through the synergy of terpenes and cannabinoids9. Research in the past has focused primarily on the cannabinoids THC and CBD, but there is increasing interest in the other secondary metabolites and their potential benefits in combination with other substances. The effect of this combination is referred to as the entourage effect6. Examples of lesser known cannabinoids include tetrahydrocannabivarin (THCV), cannabinol (CBN), cannabigerol (CBG), and cannabichromene (CBC). To date, the most important terpenes are β-myrcene, pinene, limonene, linalool, β-caryophyllene, and α-humulene10,11.

The remarkable interplay of chemical compounds was described by neurologist Ethan Russo in 2011 in a study of the entourage effect6. In his study, it is clear how even the smallest amounts of terpenes can influence the effects of cannabis flowers.


The studies of the last few years especially highlight that the cannabis plant with its effect is too complex to conclude from the appearance of cannabis flowers to their therapeutic properties3. More research is needed to accurately predict the effects of strains based on their constituents.


What is the difference between indica and sativa?

Essentially, indica and sativa cannabis strains differ in appearance, growth, and growing conditions. For many years, cannabis flowers were also said to have different effects. However, nowadays experts recommend differentiating cannabis flowers based on other characteristics. The individual THC and CBD content as well as the terpene profile of a plant are important. In addition, there is a seemingly endless selection of different cannabis flowers.

Which cannabis strain for pain?

In general, medical cannabis strains that are high in THC are more suitable for treating chronic pain than those that are high in CBD. Additionally, the terpene myrcene is known for its sedative effects, and strains with a high concentration of myrcene may be suitable for pain management6. For the therapy of pain, it does not matter whether the plant is called an indica or sativa variety.

Which cannabis requires a prescription?

Medical cannabis always requires a prescription. The only cannabis products that are freely available are those that have a THC level of less than 0.2%. These are known as CBD products. However, in over-the-counter preparations, the CBD content is also so low that a medical effect cannot be assumed. High-dose CBD extracts are considered medicinal products, so they require a prescription, but they are not considered narcotics. Therefore, they can be obtained from pharmacies with a conventional prescription.

Disclaimer and legal notice

This article is for informational purposes only and does not replace medical advice from a physician. The content is not intended to motivate self-diagnosis or self-treatment, nor to induce independent changes in current medical treatment. Canify Clinics does not make any recommendations or promote any diagnostic methods or treatments. If you wish to change your treatment, this should always be discussed with a physician. Furthermore, Canify Clinics cannot guarantee the accuracy, timeliness and balance of the content. Therefore, both the authors of the texts and Canify Clinics assume no liability for damages resulting from the independent application of the information described here.


  1. 1Piomelli, D. & Russo, E. B. The Cannabis sativa Versus Cannabis indica Debate: An Interview with Ethan Russo, MD. Cannabis Cannabinoid Res 1, 44–46 (2016).
  2. 2Nations Office Drugs, U. O. Recommended Methods for the Identification and Analysis of Cannabis and Cannabis Products. (2022)
  3. 3Sawler, J. et al. The Genetic Structure of Marijuana and Hemp. PLoS One 10, (2015).
  4. 4Leafly. Sativa vs. Indica: Was sagen Experten?
  5. 5Gloss, D. An Overview of Products and Bias in Research. Neurotherapeutics 12, 731 (2015).
  6. 6Russo, E. B. Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects. Br J Pharmacol 163, 1344–1364 (2011).
  7. 7MacCallum, C. A. & Russo, E. B. Practical considerations in medical cannabis administration and dosing. Eur J Intern Med 49, 12–19 (2018).
  8. 8Pijlman, F. T. A., Rigter, S. M., Hoek, J., Goldschmidt, H. M. J. & Niesink, R. J. M. Strong increase in total delta-THC in cannabis preparations sold in Dutch coffee shops. Addiction biology 10, 171–180 (2005).
  9. 9LaVigne, J. E., Hecksel, R., Keresztes, A. & Streicher, J. M. Cannabis sativa terpenes are cannabimimetic and selectively enhance cannabinoid activity. Sci Rep 11, (2021).
  10. 10Zagzoog, A. et al. In vitro and in vivo pharmacological activity of minor cannabinoids isolated from Cannabis sativa. Sci Rep 10, (2020).
  11. 11Jin, D., Dai, K., Xie, Z. & Chen, J. Secondary Metabolites Profiled in Cannabis Inflorescences, Leaves, Stem Barks, and Roots for Medicinal Purposes. Sci Rep 10, (2020).