Cannabinoids.

Cannabinoids are strongly lipophilic and dissolve poorly in water, so they are almost always carried in a fat. Medium-chain triglycerides act as that carrier and keep the compound in solution through the gut lumen, where mixed micelle formation governs uptake. Taking a cannabinoid preparation with dietary fat raises systemic exposure compared with a fasted dose. This is a formulation and absorption relationship, not an added biological effect.

Phospholipids from lecithin lower interfacial tension and let an oily cannabinoid extract disperse as fine droplets in aqueous gut contents. Smaller droplets present more surface area to bile salts and pancreatic lipase. Emulsified and self-emulsifying preparations are a common answer to the variability seen with plain oil solutions. The pairing is formulation convention rather than a biological interaction.

Phosphatidylcholine is used to build liposomal and phospholipid-complexed cannabinoid preparations. The phospholipid bilayer holds the lipophilic molecule and travels with the normal lipid absorption route. Formulators use it for the same reason they use lecithin, to make an oil-soluble compound behave predictably in water.

Piperine inhibits several CYP enzymes and UDP-glucuronosyltransferases that also handle cannabinoid clearance. Combining the two can raise cannabinoid blood levels above what the same dose would otherwise give. The direction is predictable from the enzymology, but the size of the shift in people has not been characterised for this specific pair. Read it as a reason to be deliberate about dosing rather than as a benefit.

Quercetin inhibits CYP3A4 and CYP2C9 in laboratory systems, and those are among the enzymes that oxidise cannabinoids in the liver. Co-exposure would be expected to slow clearance. The evidence is enzymatic rather than clinical, so this belongs in the flag column rather than the benefit column.

The body's own cannabinoid-receptor ligands are built from long-chain polyunsaturated fatty acids, and dietary fatty acid supply changes the pool available for that synthesis. EPA and DHA also form their own ethanolamide derivatives that interact with the same receptor family. Plant cannabinoids act on that system from the outside, so the two arrive at the same receptors by different routes. This is mechanistic reasoning, not a tested combination.

Melatonin and cannabinoids appear together in evening formulations because both are used around sleep timing. Their mechanisms are separate, melatonin acting at MT1 and MT2 receptors and cannabinoids at CB1, so the overlap is in the felt effect rather than the pathway. Sedation can stack, which matters for anyone driving or operating machinery.

Valerian constituents act on GABAergic signalling and cannabinoids modulate neurotransmitter release presynaptically, so drowsiness from the two can add up. No trial has measured the pair. The practical point is additive sedation, and it is worth naming rather than assuming.

Honokiol and magnolol act as positive modulators at GABA-A receptors, a separate site from the cannabinoid receptors. Both are used in calm and sleep formulations, so their subjective effects can compound. Nothing has been measured in combination.

Cannabinoid oils oxidise and degrade with light, heat and air, and tocopherols are the usual chain-breaking antioxidant added to slow that. The vitamin protects the carrier oil and the cannabinoid content of the finished product. This is shelf stability, not a physiological synergy.

Caffeine blocks adenosine receptors while cannabinoids act presynaptically at CB1 to change neurotransmitter release, and adenosine and cannabinoid signalling converge on some of the same striatal circuits. Products pair them for a stimulant plus calm effect. The interaction is described mechanistically in animal work rather than measured in people.