The bioavailability of full-spectrum cannabis products

Full-spectrum cannabis products contain a variety of natural ingredients—including cannabinoids such as CBD (cannabidiol) and THC (delta-9-tetrahydrocannabinol), terpenes, flavonoids, and other substances. Some preclinical studies and the experiences of many cannabis users over the past decades indicate that these substances interact synergistically in a variety of ways.

It is therefore important for users of cannabis products to understand how these substances are absorbed and processed in the body. This article explains some relevant technical terms and provides practical tips on how to optimize the absorption of these valuable ingredients.

So what does "bioavailability" mean? Bioavailability describes how much of an active ingredient actually reaches the bloodstream after ingestion and is actually available for action in the body. For cannabinoids, it depends heavily on the intake method, accompanying food, and individual metabolic characteristics.

Oral administration with and without first-pass effect

After oral ingestion, CBD and THC undergo various metabolic processes. An important term is the first-pass effect : When a substance is swallowed, it first enters the gastrointestinal tract and then the liver, where a large portion is broken down before entering the bloodstream.

This is how the dismantling works:

Delta-9-THC is first converted into 11-hydroxy-THC by enzymes in the liver. This substance is even more potent than the original THC and is particularly effective at crossing the blood-brain barrier.

CBD is also converted by enzymes, for example into 7-hydroxy-CBD.

When taking oral medication, it's important to distinguish between products like softgel capsules, which are swallowed directly, and full-spectrum oils (more accurately called "full-spectrum extracts"), which are held in the mouth for a while. Capsules and edible products are swallowed and pass through the gastrointestinal tract and liver, which causes much of the active ingredient to be broken down before it enters the bloodstream.

Full-spectrum extracts applied sublingually (under the tongue) or buccally (through the oral mucosa between the gums and cheek) allow for faster and greater absorption because the active ingredient is absorbed directly before the rest is swallowed and then takes the slower route through the digestive tract.

With oral absorption, a product is held in the mouth for at least 60-90 seconds. This method allows the active ingredients to enter the bloodstream directly through the well-perfused mucous membranes in the mouth. This largely bypasses the first-pass effect in the liver, allowing more CBD or THC to actually reach the body and produce a faster onset of effects.

Inhalation via vaporizer

The bioavailability of THC and CBD when inhaled via a vaporizer may be significantly higher than when ingested orally. Studies show values between 10 and 56%, depending on the device, temperature, and inhalation technique. Absorption is very rapid, as the active ingredients enter the bloodstream directly via the lungs. Vaporizers enable efficient, smokeless release of the active ingredients, with temperature control being crucial for optimal extraction and preservation of cannabinoids and terpenes.

When we inhale CBD or THC, the active ingredient enters the bloodstream directly through the lungs, initially bypassing the liver. This increases bioavailability, i.e., the amount that actually reaches the body, and the effects occur more quickly.

The bioavailability of inhalation and oral administration is difficult to compare

An important difference between inhalation and oral administration with first-pass effect lies not only in the bioavailability, but also in the type of active ingredients produced.

Inhalation: THC enters the bloodstream directly and works quickly.

Swallowing: THC is converted in the liver to 11-hydroxy-THC , which has a stronger and longer-lasting effect than the original THC

Further differences:

The effect after swallowing via the first-pass effect starts later (30-120 min), but lasts longer (up to 8 hours).

The individual effect can vary greatly depending on stomach contents, metabolism and enzyme activity.

11-Hydroxy-THC can cross the blood-brain barrier more easily, which can lead to a more intense effect.

A mere comparison of bioavailability figures is therefore misleading when it comes to evaluating inhalation versus oral intake: the type and strength of the effect of cannabis products is determined not only by the amount of active ingredient absorbed, but also by the type of conversion in the body.

Different forms of intake and their effects

Topical application (creams)

When applied to the skin (e.g., CBD or THC creams), the active ingredients penetrate the upper layers of the skin and exert their local effects. Systemic bioavailability is low, as only a small portion enters the bloodstream. However, this form could be useful for targeted local effects, as cannabinoids in the skin layers can interact with endocannabinoid receptors.

Terpenes and flavonoids: absorption and processing

Terpenes and flavonoids are not only responsible for scent, taste, and color, but also potentially generate significant synergistic effects with THC and CBD. After ingestion—for example, through inhalation or orally in full-spectrum extracts—they are transported in the blood and usually metabolized by enzymes in the liver. Those who want to consume as many terpenes and other plant compounds as possible should pay attention to a few points, which are listed below.

Practical tips for optimizing your recording

1. Choose the right intake form

Sublingual/buccal (extracts, sprays): Keep drops or spray under the tongue or between the cheek and gums for at least 60-90 seconds to ensure quick and efficient absorption.

Inhalation: Inhale at moderate temperatures (180-210 °C) in a vaporizer to quickly release cannabinoids and terpenes and achieve high bioavailability.

· Oral (capsules, edible products): Take with a fatty meal, as cannabinoids are fat-soluble and thus better absorbed. Suitable for long-lasting effects.

Topical (creams, ointments): Apply to clean, intact skin; this form acts locally, systemic absorption is very low.

2. Pay attention to product quality and workmanship

· Gentle production: Choose products that have been processed at low temperatures and, if possible, without aggressive solvents in order to preserve sensitive plant substances such as terpenes and flavonoids.

· Prefer full-spectrum products: They contain the natural interaction of many plant substances.

· Reliable, natural products: Ensure tested quality and purity to ensure declared active ingredient levels and safety.

3. Storage and handling

Store in a cool, dark and airtight place: This ensures that cannabinoids, terpenes and flavonoids remain stable and effective.

4. Adjust intake individually

· Consider the time of intake: Taking with food, especially with fat, increases absorption; taking on an empty stomach can lead to faster but lower absorption.

· Be aware of medications: Certain medications can affect the absorption and breakdown of cannabinoids – if in doubt, always seek medical advice.

Conclusion

Full-spectrum cannabis products offer a wide range of ingredients, the absorption and effects of which depend on many factors. Optimal bioavailability of cannabinoids and other plant compounds is achieved through the appropriate intake method, high-quality and carefully processed products, proper storage, individual adaptation, a conscious diet, and the avoidance of interactions.

Bioavailability can be improved by choosing the right dosage form, combining it with fatty foods, and maintaining the correct vaporization temperature. A comparison of bioavailability between inhalation and oral administration is only of limited use, as the resulting active ingredients and their effects differ significantly.

Note: This article is for general information purposes only and does not replace individual medical advice. No claims are made regarding the healing effects or treatment of any disease.

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