Medically Reviewed by
Jason Crawford

Article Last Updated on January 13, 2023

Out of the many ways of consuming cannabis in all its glory, vaporizing weed has found a cozy little nook in the cannabis community and is winning the hearts of many cannabis consumers.

Even though it’s a relatively new method of weed consumption, vaporizers and vape pens can be easily found in dispensaries in states where weed is legal. Vaporizing is considered a healthier alternative to smoking, and it’s much less complicated than dabbing, hence its popularity.

There are different types of portable vaporizers – some are designed to vape dry herbs, while others work with full-spectrum cannabis oils and concentrates or with concentrates that contain just one cannabinoid, either THC (tetrahydrocannabinol) or CBD (cannabidiol).

In this article, we’ll talk about THC vape cartridges, how they’re designed and what they contain, and we’ll give you a simple method so you can make vape juice yourself.

What’s In a THC Vape Cart?

Handheld vaporizers are made up of three parts:

  • A glass cartridge that holds the cannabis oil or vape juice. It can be refilled, unless it’s a disposable vape pen;
  • A battery, which powers up an atomizer that vaporizes the oil;
  • A mouthpiece to draw the vapor from.

Now, let’s see the details of what THC vape carts usually contain.

THC Oil or Vape Juice

Most commonly, THC vape carts are filled with one gram of a THC concentrate (distillates, CO2 hash oil, BHO, live resin, shatter, or rosin). The most common concentrates used are CO2 hash oil or distillates. Both are quite viscous, so to be vaped properly, they are usually diluted with cutting agents. For example, you may read on the label that the THC cart is 97% THC and the remaining 3% will be cutting agents. However, distillates, for example, are okay on their own and don’t need any thinners.

THC vape carts can also be filled with vape juice. You may know that vape juice usually refers to the nicotine-containing e-liquid used with e-cigarettes. However, ever since cannabis vaporizers came onto the scene, the term “vape juice” has expanded its scope. In the context of cannabis products, vape juice contains cannabinoids. The base of vape juice is either propylene glycol (PG) or vegetable glycerin (VG), and a THC concentrate.

Cutting Agents

In order to improve the flavor, viscosity, and effects of vaping, most manufacturers add solvents and additives. These are added to THC concentrates only, not vape juice, because concentrates are typically thicker and need to be thinned out. 

  • Terpenes are added to improve the flavor, but also to boost the entourage effect. They can be either cannabis-derived or food-derived, and they are considered to be safe;
  • Coconut oil is also sometimes added because it’s good at thinning out the cannabis concentrate to optimize it for vaping;
  • The most commonly used thinners, though, are polyethylene glycol (PEG), vegetable glycerin (VG), and propylene glycol (PG). There have been some concerns regarding the safety of these cutting agents, particularly about PEG or PEG 400. PEG 400 can release higher levels of acetaldehyde and formaldehyde when it starts to degrade, which can be considered harmful.

How to Make Your Own THC Vape Juice

Believe it or not, you can make your own vape juice at home. Admittedly, making it is not simple, but it’s totally doable and the results are quite rewarding. Once you learn the proper method, you can make your own unique blends and experiment with different strains. Let’s begin!

Before you start doing anything, making the cannabinoid extraction is the most basic step. The safest and most effective ingredient to use for the extraction is food-grade vegetable glycerin. We advise you to not use glycerin that is non-food grade as its safety is questionable at best.

For the extraction, you’ll need:

  • Vegetable glycerin (VG)
  • Vegetable oil
  • Cannabis flowers
  • Large pot
  • 1 medium Pyrex jar
  • 3 mason jars
  • 2 thermometers
  • Cheesecloth
  • Fine mesh strainer
  • Rubber spatula


  1. Break up the cannabis flowers into smaller pieces, put them into a Pyrex jar, and cover the buds with vegetable glycerine. Make sure they are saturated in the glycerine by mixing well, but don’t overflow the jar.
  1. Next, pour about 1-2 inches worth of vegetable oil in a large pot on the stove and heat on a medium setting. Place one of the thermometers in the oil and wait for the temperature to reach 219.8°F (104°C). 
  1. Once the temperature in the pot is stable, place the other thermometer into the Pyrex jar and carefully place it in the pot with the oil.
  1. The temperature in the Pyrex jar should reach 179.6°F (82°C) and remain stable for 45 minutes, just enough so that the inactive cannabinoids, THCA and CBDA, and terpenes can be extracted effectively from the buds.
  1. After the 45 minutes have passed, take out the Pyrex jar from the pot and let it cool down for a few minutes. When it’s cooled enough, strain it into one of the mason jars to separate the vegetable glycerin from the plant material. Use the spatula to press gently on the buds so that you can separate as much of the glycerine as you can. 
  1. Repeat the same process two more times with the same buds using fresh glycerine so you can extract all the remnants of the active ingredients.
  1. When that’s done, in order to purify the glycerin from tiny particles, layer several pieces of cheesecloth over the other mason jar and strain the glycerine again.
  1. The second to the last step is to decarb your vape juice to “activate” THCA and CBDA into THC and CBD, respectively. To decarb the glycerine, put it back into the pot with the oil at a temperature of 219.8°F (104°C) for 30 minutes.
  1. Finally, take it out and let it cool. Pour it into a clean and sterile mason jar, load up your cartridge, and enjoy your creation! Top up your cartridge when needed from the mason jar.

The Takeaway and a Word of Caution

The reason why handheld vaporizers are so popular is because they are convenient to use and they’re discreet. THC cartridges, in particular, allow you to consume this active ingredient in a controlled way so that you can get all the benefits. 

However, one word of caution would be to always buy your carts from reputable manufacturers. Shady retailers may sell THC carts with harmful additives, so always look for high-quality products from trusted sources. In the meantime, you can always try to make your own vape juice.

A passionate advocate for the benefits of cannabis. Fraser Horton, who has a background in botany and a strong love of nature, has spent years researching how cannabis affects the body and mind. He established Leaf Nation in 2020, where he has devoted himself to educating people about the legalisation of marijuana and its safe and responsible use. Fraser is committed to highlighting cannabis’ potential for improving wellness and working to dispel the stigma associated with its use.


The information presented on this page is provided as a public service to aid in education and is derived from sources believed to be reliable. Readers are responsible for making their own assessment of the topics discussed here. In no event shall Leaf Nation be held reliable for any injury, loss or damage that could happen if using or abusing drugs.