Issue link: https://www.e-digitaleditions.com/i/883179
28 October 2017 Tablets & Capsules nature and hydrophobicity. Isolating the oil from the plant is commonly done by supercritical fluid extraction (SFE) using CO 2 or by ethanol extraction. The oil is then processed to remove the plant waxes and decarboxylated to convert the acid forms of the phytocannabidnoids to more usable forms. Formulating tablets and capsules So, we have the API in an oil form that's pretty easy to fill into capsules, right? Well, kind of. Once I got to talk- ing with long-time contacts in the capsule area, I hear, "We can't do business any longer," due to the nature of my company and API. Nothing personal, they tell me, they just don't want any assets frozen or taken by the fed- eral government. "Oh, and good luck." But we did find companies that would do business with us, and after buying some capsule shells and liquid capsule fillers, we're all set, right? Not exactly. While the majority of THC capsules are indeed simply filled with oil, there is room for improvement. For that, we turn to a variety of materials and strategies to enhance absorption. One approach is to make an emulsion or a self-emulsify- ing drug delivery system (SEDDS). I'm not at liberty to divulge the specifics of our formulation methods, but even people with no experience in this area could figure out some strategies after searching the literature. What about capsule leakage? Although most cannabis- based capsules on the market today use straight THC- CBD oil, few cannabis manufacturers, I suspect, have a capsule bander and have likely never heard of one. And that's OK if your formulation is a semi-solid capsule like ours and not prone to leakage. Other companies dilute the THC-CBD oil with medium-chain triglycerides (MCTs) such as coconut oil or with polyethylene glycol (PEG) to improve the filling characteristics. Yet others add powder to the oil and market their products as leak- free. At the other ends of the spectrum are full-fledged pharma formulations with a list of chemicals that the aver- age cannabis customer doesn't recognize and formulations that use pure plant materials with no additives, which a variety of patients prefer, even though there are many safe, effective additives that would enhance absorption. So much for capsules. How about tablets? First, let's specify the API load. But there is no agreed-upon dosage of cannabinoids for a tablet or a capsule. It varies from state to state and country to country. That's what you get when states take jurisdiction from the federal government for a Schedule 1 substance. Odd, isn't it? In New York, my home base, 10 milligrams (mg) is the maximum allowable dose for cannabinoids. Tablets are the same dose in Colorado and because Colorado law caps the amount of cannabinoid per package at 100 mg, they mar- ket 10 of these 10 mg tablets in a bottle. Other states have different laws, so it gets complicated. (We got our capsules to market after undergoing a review by the New York government and without sending a truckload of paperwork to the FDA.) Fortunately, 10 mg of API (about 17 mg of oil) is not too tough to deliver. Or is it? At about 65 percent purity, cannabis oil is a bit viscous, but nothing that a little heat won't cure. And while loading oil into powders is cer- tainly not mainstream, it's nothing new. Any formulators worth their weight in microcrystalline cellulose should be able to load 17 mg of oil into a tablet that people can still swallow. In fact, a variety of materials are a perfect fit for the task, including specialty silicas, celluloses, and even lactoses. Just don't hit the formulation too hard on the tablet press or you will express the oil right out of the tablets and make a mess. Modifying the API Are we happy to have formulated a stable 65 percent pure oil into a tablet? Sure, but once again there's room for improvement in solubility/absorption, tablet size, etc. The first step is to purify the API. Who wants 35 percent of miscellaneous compounds in their API, especially com- pounds that haven't been identified and may not do any- thing in the formulation? Actually, a lot of people want just that, seeking what's been dubbed the "entourage effect" [2]. The idea here is that those non-API compounds work together to provide superior therapeutic results. That has not been scientifically proven for this plant extract or any indications, but the people we know as "label readers" in the nutraceutical market believe it's the way to go. Regardless of your thoughts on "natural versus chemical," when it comes to plant compounds, we must make some Cannabis oil before and after distillation Photo by Colleen Mairéad Hughes This high-viscosity THC distillate is 90 percent pure. Photo by Colleen Mairéad Hughes