Medical Cannabis Strains

There are thousands of different cannabis strains worldwide; most of them are hybrids of their ancestors: Sativa and Indica. Patients looking for the right strain for them may “get lost” trying to differentiate between them.

What Is Medical Cannabis?

In the discourse on medical cannabis, there is a large gap between the concepts used by the public and the concepts used by the world of research and medicine. And although the medicinal properties of cannabis have been known and people have used them for approximately 5,000 years, there is still a debate about the taxonomy (description and classification) of the cannabis plant1 and the therapeutic effects of its various ingredients. In the past, medical cannabis strains were defined according to their shape: the “Indica” strain was characterized by low and wide growth, while the “Sativa” strain was characterized by tall and narrow growth.

Some see cannabis as a single species with multiple strains, while others see it as having up to three different strains of origin: Cannabis Sativa, Cannabis Indica, and Cannabis Ruderalis2. Cannabis Sativa and Cannabis Indica are the most used3.

What Medical Cannabis Strains Are There?

There are thousands of different cannabis strains worldwide, which are also used for medicinal purposes. Most of them are crossbreeding of their ancestors – Sativa and Indica. Patients seeking to find the most effective strain for them may “get lost” trying to differentiate between them. Moreover, the word “strain” is not the recommended term when adjusting the treatment. After so many years of cultivation and use, the names of the strains sold in the market are often based on the morphology of the plant, height, color, etc., and classified according to its origin (“Indica-based or “Sativa-based”)4.

But the more serious issue is that there seems to be no consistency between the strains’ quality levels. The same strain grown by 100 different growers can potentially become 100 different products. Patients who have found that a certain strain from a specific grower is the most effective for them may find that the same strain from another grower or even from the same grower but from a different production batch may not have the same effect.

Are There Any Differences Between the Cannabis Strains?

Another belief that has become common among the public is that Sativa-based cannabis tends to elevate the mind and cause psychoactive effects, while Indica-based cannabis tends to induce relaxation. In practice, experts in the field discourage the use of medical cannabis according to this division because there is no clinical research to support it5.

In addition, a study comparing the genetics of Indica-based strains versus Sativa-based strains showed no significant genetic difference between them. Furthermore, there were no significant differences in the concentrations of phytocannabinoids they contained, but only a small difference in the concentrations of terpenes5.

The names of the strains sold in the market are usually based on the morphology of the plant and classified according to its origin (“Indica-based” or “Sativa-based”).

The Cannabinoids, Phytocannabinoids, and Terpenoids

Although the studies focus on THC and CBD cannabinoids, there are over 500 different compounds in medical cannabis types. The compounds include more than 100 different phytocannabinoids6, whose therapeutic effect on pain has not yet been studied, and close to 100 types of terpenoids7 in various concentrations within the different “strains.” The terpenes are responsible for the aroma of the cannabis8. In the past, THC and CBD were thought to be the only active cannabinoids. Based on all the knowledge we have today, the popular opinion is that probably a large part of the components of cannabis has a therapeutic effect4.

Therefore, when referring to a certain cannabis “strain,” the preferred clinical reference is chemotype9. A term that refers to the concentration of the plant’s active ingredients and takes into account the cannabinoids and terpenes, as well as the other ingredients that contribute to the effects of cannabis.

What Are the Positive Effects and Side Effects of Cannabis Strains?

The following claims do not have support in clinical studies yet; however, they are supported by the guidelines and records of Protocol 1062 of the Israeli YAKAR – the authorized body in the Israeli Ministry of Health to issue medical cannabis licenses to patients for medical purposes. “Strains” of Sativa genetic origin are stimulants – stimulating appetite, stimulating creativity, reducing depression, and recommended for use during the day. In contrast, “strains” of Indica genetic origin are depressants – relaxing, sedative, anxiety-reducing, pain-reducing, and recommended for use at night. However, except for one study conducted in the Netherlands on Coffee Shops strains and medical cannabis strains, studies have shown a slight difference in the terpene amount between strains of Sativa genetic origin and Indica genetic origin1. But the researchers reported that the compared strains were not pure but hybrids; therefore, it is necessary to conduct an orderly study and use strains whose genetic origin is pure. However, as mentioned, such strains do not exist anymore.

How to Determine the Right Cannabis Strain for Patients?

The categories for choosing are determined by the concentration of two phytocannabinoids: THC and CBD. The THC-rich strains have three categories: T20/C4, T15/C3, and T10/C2. The balanced strains also have three categories: T10/C10, T5/C5, and T3/C3. The CBD-rich strains have five categories: T1/C28, T0/C24, T1/C20, T3/C15, and T5/C10. Most chronic pain patients with a medical cannabis license prefer to buy strains that are THC-rich10-11. However, no research has yet been done to show that different strains have different clinical potentials.

In the past, people tended to think that THC and CBD were the only active cannabinoids.

How to Choose the Right Treatment with Medical Cannabis?

Let’s not talk about the right strain but the right treatment for each patient. After all, in the end, treatment using medical cannabis is meant to bring about the best result, which is adapted to every patient’s needs. We know that the effect of cannabis is subjective and may differ from person to person, even if two patients suffer from the same indication and have a similar profile. Therefore, the recommendations and opinions of certain patients are not necessarily relevant to other patients. Treatment with medical cannabis starts gradually (titration). At each stage, the body is allowed to adapt to the dose with reference to two parameters: whether there was a significant improvement and whether there were tolerable side effects (or none at all). Titration can be performed independently, but it is better to be accompanied by qualified medical personnel, such as nurses.

What Is the Difference Between Medical Cannabis and Recreational Cannabis?

Are there different types of cannabis strains? “Medical” cannabis marketed for treatment purposes, and “regular” cannabis sold as a “light drug” for recreational purposes? The truth is that all cannabis is medicinal as long as it is grown under the appropriate conditions, meaning it has the potential for a broad therapeutic ability and the potential to alleviate various medical problems. And those who have read about the history of cannabis know this. The differences are in the method of growing the cannabis and the level of maintaining the scientific and health principles in the process. There are three differences between medical cannabis and recreational cannabis:

  1. Legality of use: In some countries, cannabis is considered a dangerous drug and is prohibited for recreational use. For medical treatment purposes, a special license or prescription must be obtained (according to the rules and regulations of each country).
  2. Reason for use: Cannabis users for therapeutic purposes prefer only to receive its medical effects without the psychoactive side effects. Recreational consumers use it for the exact opposite reason.
  3. Method of use: Medical cannabis for therapeutic purposes is approved for administration by inhalation (medical inhaler, smoking, and vaporization) as well as ingestion (oil). Those who use cannabis to get high do so mainly through vaping and smoking.
  1. Ragazzi, Taciana CC, et al. “Cannabis use as a risk factor for psychotic‐like experiences: A systematic review of non‐clinical populations evaluated with the Community Assessment of Psychic Experiences.” Early intervention in psychiatry 12.6 (2018): 1013-1023.
  2. Talkowski, Michael E., et al. “A network of dopaminergic gene variations implicated as risk factors for schizophrenia.” Human molecular genetics 17.5 (2008): 747-758.
  3. Carney, Rebekah, et al. “Cannabis use and symptom severity in individuals at ultra high risk for psychosis: a meta‐analysis.” Acta Psychiatrica Scandinavica 136.1 (2017): 5-15.
  4. World Health Organization, and WHO Expert Committee on Drug Dependence. WHO Expert Committee on Drug Dependence: fortieth report. World Health Organization, 2018.
  5. Arboleda, Maria Fernanda, et al. “Medical cannabis in supportive cancer care: Lessons from Canada.” Supportive Care in Cancer 28.7 (2020): 2999-3001.
  6. Ramaekers, J. G., N. L. Mason, and E. L. Theunissen. “Blunted highs: pharmacodynamic and behavioral models of cannabis tolerance.” European Neuropsychopharmacology 36 (2020): 191-205.
  7. Scott, J. Cobb, et al. “Association of cannabis with cognitive functioning in adolescents and young adults: a systematic review and meta-analysis.” JAMA psychiatry 75.6 (2018): 585-595.
  8. World Health Organization, and WHO Expert Committee on Drug Dependence. WHO Expert Committee on Drug Dependence: fortieth report. World Health Organization, 2018.
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  10. Aviram J, Pud D, Gershoni T, Schiff‐Keren B, Ogintz M, Vulfsons S, Yashar T, Haim‐Moshe A, Brill S, Amital H, Goor‐Aryeh I, Robinson D, Green L, Segal R, Fogelman Y, Tsvieli O, Yellin B, Vysotski Y, Morag O, Tashlykov V, Sheinfeld R, Goor R, Meiri D, Eisenberg E. Medical Cannabis Treatment for Chronic Pain: Outcomes and Prediction of Response. Eur J Pain 2020.
  11. Aviram J, Pud D, Schiff-Keren B, Ogintz M, Vulfsons S, Yashar T, Adahan M, Brill S, Amital H, Goor-Aryeh I, Robinson D, Green L, Segal R, Fogelman Y, Tsvieli O, Eisenberg E. The Israeli multi-center registry of medical cannabis (MC) for chronic pain: current findings. 10th Congress of the European Pain Federation (EFIC)  . Copenhagen, Denmark, 2017.