Types of Cannabis and Health Risks
Steven Gans, MD is board-certified in psychiatry and is an active supervisor, teacher, and mentor at Massachusetts General Hospital.
With states legalizing across the country, many people are starting to learn that there are multiple varieties of the cannabis plant, sometimes called “marijuana”, and they can be prepared in a variety of ways. The potency of cannabis can vary greatly from one plant to another and from one preparation to another. The route of administration can strongly affect the intensity of marijuana’s effects.
One person’s experience of taking marijuana can be completely different from that of someone else.
Often simply called weed or pot, this is the unprocessed form of cannabis. Weed consists of the dried leaves and buds of the female Cannabis sativa and Cannabis indica plants.
It has a very pungent and recognizable odor, both in its unburnt state and while being smoked. This odor is quite unlike kitchen herbs, although weed is sometimes “cut” (mixed) with benign kitchen herbs such as oregano and parsley when sold in the underground market.
Weed is commonly smoked in hand-rolled cigarettes, known as joints. The lumpy texture of weed can be felt through the tobacco rolling paper. This is one of the characteristics that can differentiate a joint from a hand-rolled tobacco cigarette.
Hashish and weed can be mixed with rolling tobacco, which is a soft, moist, sticky tobacco preparation designed for hand-rolling. It may also be mixed with the dry tobacco from deconstructed cigarettes. This mixture is referred to as a “spliff”.
Weed, hashish, and hashish oil can be smoked in pipes, water pipes, and bongs, or mixed with tobacco and smoked in a chillum. Some young adults have also used e-cigarettes to inhale marijuana through “vaping.”
Hashish, or hash for short, is a preparation of marijuana made from the resin of the Cannabis sativa or Cannabis indica plant. The resin is dried into blocks of hashish, producing an oily, solid substance.
Cannabis resin can be referred to by the names for the specific type of hash, rather than the generic names of hashish or pot. These different names for hashish include black, goldseal black, redseal black, and Morrocan (Rocky for short).
Hashish is often warmed, crumbled, and rolled together with tobacco. It may also be smoked in a pipe, bong, or chillum.
There are several different types of hashish. The colors range from dark brown or almost black, through various shades of brown, to a dirty yellowish color.
The appearance of different types of hashish can vary as well. Some may look dark and shiny (a bit like licorice) and some may be lighter and dull or matte (a bit like a soup stock cube). The texture of hashish also varies from quite dry and hard, like a piece of fudge, to moist and pliable, like modeling clay.
As with weed, hashish has a very distinctive, pungent odor. It is one of the easiest ways of identifying it as a form of marijuana. The appearance of hashish is so varied that novice users are often duped into buying licorice or other cheap, benign substances that look similar.
Hashish oil, or hash oil, is the strongest form of marijuana and is the least common form of the drug. It is sold in tiny bottles or sealed plastic bags.
Only a small amount is needed to produce the effects of marijuana. Typically, hash oil is smoked in a pipe or painted onto cigarettes or joints.
Learn how to identify the several types of marijuana, a variety of cannabis preparations, risks, and benefits.
Sativa vs. Indica: What to Expect Across Cannabis Types and Strains
Things to consider
The two main types of cannabis, sativa and indica, are used for a number of medicinal and recreational purposes.
Sativas are known for their “head high,” an invigorating, energizing effect that can help reduce anxiety or stress and increase creativity and focus.
Indicas are typically associated with full-body effects, such as increasing deep relaxation and reducing insomnia.
Although research examining these effects is limited, it appears these plants have more in common than previously thought.
In other words, the category, or type, of cannabis may not be the greatest indicator of the effects you’ll experience.
Here’s how to find the right plant for your needs, strains to consider, potential side effects, and more.
What should you look for to understand strain effects?
The often-applied rule of thumb is that sativas are more invigorating and energizing, while indicas are more relaxing and calming — but it isn’t really that simple.
Individual plants produce varying effects, even among the same type of cannabis. It all depends on the plant’s chemical composition and the growing technique used.
Instead of looking at the type alone — sativa or indica — look at the description the grower and dispensary provide.
Oftentimes, the plant types are broken down into specific strains, or breeds.
Strains are distinguished by their individual cannabinoid and terpene content. These compounds are what determine the strain’s overall effects.
Cannabis plants contain dozens of chemical compounds called cannabinoids.
These naturally occurring components are responsible for producing many of the effects — both negative and positive — of cannabis use.
Researchers still don’t understand what all of the cannabinoids do, but they have identified two main ones — tetrahydrocannabinol (THC) and cannabidiol (CBD) — as well as several less common compounds.
- THC. THC is the main psychoactive compound in cannabis plants. It’s responsible for the “high” or state of euphoria associated with cannabis use. Levels of THC have been increasing as growers try to create hybrids with a greater concentration of the compound.
- CBD. CBD is non-psychoactive. It doesn’t cause a “high.” However, it may produce many physical benefits, such as reducing pain and nausea, preventing seizures, and easing migraine.
- CBN. Cannabinol (CBN) is used to ease symptoms and side effects of neurological conditions, including epilepsy, seizures, and uncontrollable muscle stiffness.
- THCA. Tetrahydrocannabinol acid (THCA) is similar to THC, but it doesn’t cause any psychoactive effects. Its potential benefits include reducing inflammation from arthritis and autoimmune diseases. It may also help reduce symptoms of neurological conditions like Parkinson’s disease and ALS.
- CBG. Cannabigerol (CBG) is thought to help reduce anxiety and symptoms of obsessive-compulsive disorder, post-traumatic stress disorder, and depression.
A great deal of attention is paid to the amount of THC and CBD in a given strain, but newer research suggests that terpenes may be just as impactful.
Terpenes are another naturally occurring compound in the cannabis plant.
The terpenes present directly affect the plant’s smell. They may also influence the effects produced by specific strains.
According to Leafly, common terpenes include:
- Bisabolol. With notes of chamomile and tea tree oil, the terpene bisabolol is thought to reduce inflammation and irritation. It may also have microbial and pain-reducing effects.
- Caryophyllene. The peppery, spicy molecule may reduce anxiety, ease symptoms of depression, and improve ulcers.
- Linalool. Linalool is said to help improve relaxation and boost mood with its floral notes.
- Myrcene. The most common terpene, this earthy, herbal molecule may help reduce anxiety and insomnia so you can sleep better.
- Ocimene. This terpene produces notes of basil, mango, and parsley. Its primary effects may include easing congestion and warding off viruses and bacteria.
- Pinene. As the name suggests, this terpene produces an intense pine aroma. It may help boost memory, reduce pain, and ease some of the not-so-pleasant symptoms of THC, such as nausea and coordination problems.
- Terpinolene. Cannabis with this compound may smell like apples, cumin, and conifers. It may have sedative, antibacterial, and antifungal properties.
- Limonene. Bright, zippy citrus notes come from this terpene. It’s said to improve mood and reduce stress.
- Humulene. This terpene is deeply earthy and woody, like hops or cloves. Cannabis strains with this molecule may reduce inflammation.
- Eucalyptol. With notes of eucalyptus and tea tree oil, this molecule is refreshing and invigorating. It may also reduce inflammation and fight bacteria.
- Origin:Cannabis sativa is found primarily in hot, dry climates with long sunny days. These include Africa, Central America, Southeast Asia, and western portions of Asia.
- Plant description: Sativa plants are tall and thin with finger-like leaves. They can grow taller than 12 feet, and they take longer to mature than some other types of cannabis.
- Typical CBD to THC ratio: Sativa often has lower doses of CBD and higher doses of THC.
- Commonly associated effects of use: Sativa often produces a “mind high,” or an energizing, anxiety-reducing effect. If you use sativa-dominant strains, you may feel productive and creative, not relaxed and lethargic.
- Daytime or nighttime use: Because of its stimulating impact, you can use sativa in the daytime.
- Popular strains: Three popular sativa strains are Acapulco Gold, Panama Red, and Durban Poison.
- Origin:Cannabis indica is native to Afghanistan, India, Pakistan, and Turkey. The plants have adapted to the often harsh, dry, and turbulent climate of the Hindu Kush mountains.
- Plant description: Indica plants are short and stocky with bushy greenery and chunky leaves that grow wide and broad. They grow faster than sativa, and each plant produces more buds.
- Typical CBD to THC ratio: Indica strains often have higher levels of CBD and less THC.
- Commonly associated effects of use: Indica is sought after for its intensely relaxing effects. It may also reduce nausea and pain and increase appetite.
- Daytime or nighttime use: Because of its deep relaxation effects, indica is better consumed at night.
- Popular strains: Three popular indica strains are Hindu Kush, Afghan Kush, and Granddaddy Purple.
Each year, cannabis growers produce new and unique strains from different combinations of parent plants. These cannabis hybrids are often grown to target specific effects.
- Origin: Hybrids are typically grown on farms or greenhouses from a combination of sativa and indica strains.
- Plant description: The appearance of hybrid strains depends on the combination of the parent plants.
- Typical CBD to THC ratio: Many hybrid cannabis plants are grown in order to increase the THC percentage, but each type has a unique ratio of the two cannabinoids.
- Commonly associated effects of use: Farmers and producers select hybrids for their unique impacts. They can range from reducing anxiety and stress to easing symptoms of chemotherapy or radiation.
- Daytime or nighttime use: This depends on the predominant effects of the hybrid.
- Popular strains: Hybrids are typically classified as indica-dominant (or indica-dom), sativa-dominant (sativa-dom), or balanced. Popular hybrids include Pineapple Express, Trainwreck, and Blue Dream.
A third type of cannabis, Cannabis ruderalis, also exists. However, it isn’t widely used because it usually doesn’t produce any potent effects.
- Origin: Ruderalis plants adapt to extreme environments, such as Eastern Europe, Himalayan regions of India, Siberia, and Russia. These plants grow quickly, which is ideal for the cold, low-sunlight environments of these places.
- Plant description: These small, bushy plants rarely grow taller than 12 inches, but they grow rapidly. One can go from seed to harvest in little more than a month.
- Typical CBD to THC ratio: This strain typically has little THC and higher amounts of CBD, but it may not be enough to produce any effects.
- Commonly associated effects of use: Because of its low potency, ruderalis isn’t routinely used for medicinal or recreational purposes.
- Daytime or nighttime use: This cannabis plant produces very few effects, so it can be used at any time.
- Popular strains: On its own, ruderalis isn’t a popular cannabis option. However, cannabis farmers may breed ruderalis with other cannabis types, including sativa and indica. The plant’s rapid growth cycle is a positive attribute for producers, so they may want to combine more potent strains with ruderalis strains to create a more desirable product.
Potential side effects and risks
Although cannabis use is often associated with potential benefits, it can also produce unwanted side effects.
- dry mouth
- dry eyes
- increased heart rate
- decreased blood pressure
Most of these effects are associated with THC, not CBD or other cannabinoids. However, any cannabis product can produce side effects.
The method of use may increase your risk for side effects, too.
For example, smoking or vaping cannabis can irritate your lungs and airways. This may lead to coughing and respiratory problems.
Oral cannabis preparations, such as gummies or cookies, are less likely to affect your overall respiratory health.
However, the effects are felt more slowly and typically aren’t as strong.
Sativa and indica are the two main types of cannabis plants. The often-applied rule of thumb is that sativas are more invigorating and energizing, while indicas are more relaxing and calming — but this is an immense oversimplification. Here's how to find the right plant for your needs, strains to consider, and more.