Safety14 min readAugust 7, 2026

Koi CBD Review 2026: An FDA Warning Letter, Two DEA Schedulings, and the Most Expensive CBD We've Priced

Koi has good lab testing and one of the more generous return policies in hemp. It also received an FDA warning letter declaring its Delta 8 Gummies adulterated, built much of its range on cannabinoids the DEA has since placed in Schedule I, and charges roughly two and a half times what the cheapest CBD in our comparison costs per milligram.

By Med Consumer Watch Team

Koi CBD is a California hemp company selling CBD tinctures, gummies, topicals, vapes and pet products, alongside a large range of intoxicating cannabinoid products — Delta-8, Delta-9, THC-P and THCA flower, and historically HHC and THC-O. Its flagship broad-spectrum tincture is $69.99 for 1,000mg — 7.0 cents per milligram. It ships within the United States only. We checked its catalogue, pricing, policies and regulatory record on August 7, 2026. Disclosure: this page contains affiliate links and we earn a commission if you buy through them. That is our only relationship with Koi. The company did not review this page. This is the most cautionary review we have written in this category, and the reasons are documented rather than inferred. The FDA issued Koi CBD LLC a warning letter on July 18, 2023, following an inspection of its Norwalk, California facility in December 2022. The letter determined that Koi brand "Delta 8 Gummies" and Hemp Living brand "Pot Rocks" were adulterated because they contain an unsafe food additive — there is no food additive regulation authorising delta-8 THC in conventional foods, and the FDA stated it was aware of no basis to conclude it is generally recognised as safe. Two cannabinoids Koi has sold are now Schedule I. The DEA has stated that THC-O acetate is not hemp because it does not occur naturally in the plant, and in 2026 it listed HHC in Schedule I with its own drug code, effective May 4, 2026, on the reasoning that tetrahydrocannabinols made by chemical conversion do not qualify as hemp even when hemp-derived. The affiliate materials we were given still point at HHC and THC-O landing pages. We are not linking to those products, and we would not buy them. And the CBD itself is expensive — 7.0 cents a milligram, against 2.7 for the cheapest brand in our comparison.

The FDA Warning Letter

This is a matter of public record, not interpretation, and it is the single most important fact about this brand. The FDA inspected Koi CBD LLC's facility in Norwalk, California from December 12–15, 2022. On July 18, 2023, it issued warning letter #651252. What it found. The letter determined that Koi brand "Delta 8 Gummies" and Hemp Living brand "Pot Rocks" are adulterated within the meaning of the Federal Food, Drug, and Cosmetic Act, because they bear or contain an unsafe food additive. The reasoning is straightforward and hard to argue with. There is no food additive regulation that authorises the use of delta-8 THC in conventional food, and the FDA stated it is not aware of any basis to conclude that delta-8 THC is generally recognised as safe (GRAS) for that use. Under US food law, an additive that is neither approved nor GRAS makes the food adulterated. That is a legal conclusion about the product, not a marketing dispute. What this does and does not mean. It does not mean the gummies poisoned anyone, and it is not a recall. It means a federal regulator formally told this company that a product it was selling for consumption was adulterated under the law. For a brand asking you to eat its products, that is the most serious thing on its record — and it is the only FDA warning letter we have found across the hemp brands we have reviewed on this site.

Put this next to the other brands we have covered. Our Aspen Green review noted approvingly that we found no FDA warning letter, in an industry that has collected many. Koi has one, naming a specific product, with a specific finding of adulteration. When you are choosing between hemp brands — a category with very little external accountability — a federal enforcement record is one of the few genuinely hard signals available, and it should carry weight.

You can check this yourself for any company in this industry, and it takes two minutes: search the FDA's warning letter database for the company name. It is a public, searchable record of every letter the agency has issued. In a market where almost every quality claim is self-reported, the warning-letter database is one of the few sources that is neither marketing nor a review site.

The Cannabinoids That Are No Longer Legal

Koi built a substantial part of its business on cannabinoids beyond CBD. Several of them have since been ruled out from under it. THC-O acetate: Schedule I. The DEA has stated that delta-8 THC-O and delta-9 THC-O do not fall within the definition of hemp, because they do not occur naturally in the cannabis plant and are therefore synthetically derived. They are controlled substances. HHC: Schedule I, effective May 4, 2026. In 2026 the DEA listed hexahydrocannabinol in Schedule I and assigned it its own drug code. Its stated reasoning is broad and important: tetrahydrocannabinols produced through chemical conversion do not qualify as "tetrahydrocannabinols in hemp" even when the starting material is hemp. That logic reaches well beyond HHC. Delta-8 sits in a different and less settled position. Unlike THC-O, hemp-derived delta-8 has not been declared a controlled substance federally on the same basis — but it is the subject of the FDA warning letter above, it is banned or restricted in a substantial number of states, and it is squarely in the path of the November change below. And on November 12, 2026 — 97 days from this review — the ground shifts again. Public Law 119-37 redefines hemp so that finished products containing more than 0.4 milligrams of total THC per container cease to qualify. Effectively every intoxicating product in this catalogue exceeds that by a wide margin.

THC-O acetate — DEA: not hemp, Schedule I. Do not buy it.
HHC — DEA: Schedule I with its own drug code, effective May 4, 2026. Do not buy it.
Delta-8 THC — not federally scheduled on the same basis, but subject to Koi's FDA warning letter, banned or restricted in many states, and above the incoming 0.4mg threshold.
Delta-9, THC-P, THCA flower — all above the 0.4mg-per-container limit taking effect November 12, 2026.
Plain CBD and broad-spectrum (THC-free) products — the part of the range unaffected by any of the above.

The affiliate program materials we were supplied for this review still list landing pages for HHC gummies and THC-O. We have not linked to them and will not. If you encounter any retailer still offering HHC or THC-O, understand that the DEA's position is that these are Schedule I controlled substances — the legal exposure for possession sits with you, not the shop that sold them. Check what you are actually being sold rather than trusting a product category page that may not have been updated.

There is also a specific safety finding on THC-O worth knowing regardless of its legal status. Research published in the Journal of Medical Toxicology in January 2023 found that combusting THC-O produces ketene, a potent lung toxicant — the same compound produced by burning vitamin E acetate, which is widely considered the cause of the 2019–20 EVALI vaping injury outbreak. Vaping or smoking THC-O is not a legal grey area with an unknown risk profile; it is a legal grey area with a specific identified hazard.

What the Delta-8 Safety Data Actually Shows

Because delta-8 is the product the FDA letter named, and because it remains widely sold, the safety record deserves to be set out with the actual numbers. FDA adverse event reports: 104 reports involving delta-8 THC products between December 1, 2020 and February 28, 2022. National poison control centres: 2,362 delta-8 exposure cases between January 1, 2021 and February 28, 2022. What the adverse events were: hallucinations, vomiting, tremor, anxiety, dizziness, confusion, and loss of consciousness. How serious: 55% of cases reported to the FDA and 70% of poison centre cases required evaluation at a healthcare facility. 18% required hospitalisation — including children admitted to intensive care. Why children keep appearing in this data. These products are sold as gummies, sweets and infused snacks, in packaging that a child cannot distinguish from confectionery, and a single piece can contain a large adult dose. The FDA has specifically raised concern about delta-8 products in forms that appeal to children.

If there are children in your home and any intoxicating hemp product is in it, the packaging is not a safety feature. Store these products locked and out of reach, treat them exactly as you would a prescription medication, and know that a paediatric ingestion is an emergency — call Poison Control on 1-800-222-1222 immediately rather than waiting to see what happens. An 18% hospitalisation rate across reported cases, with ICU admissions among children, is not a theoretical risk.

One more thing that catches people out: delta-8 and every other THC isomer in this catalogue will produce a positive drug test. Standard immunoassay panels do not distinguish delta-8 from delta-9 — they detect THC metabolites. If your employment, custody arrangements, professional licence or probation depend on a clean test, these products are not a loophole and treating them as one has cost people their jobs.

Pricing: Expensive, Even Before the Discount

Set against the other hemp brands we have priced on this site, Koi's CBD is the costliest per milligram we have found. Checked August 7, 2026.

Brand | Product | Price | CBD | Cost per mg
Koi — list price | Naturals Broad Spectrum tincture, 30ml | $69.99 | 1,000mg | 7.0 cents
Koi — with the 40% sitewide promo | same | ~$42.00 | 1,000mg | ~4.2 cents
Aspen Green (our review, August 7, 2026) | Extra Full Spectrum, 30ml | $144.99 | 3,000mg | 4.8 cents
Vena CBD (our review, August 7, 2026) | Full Spectrum, 30ml | $39.95 | 1,500mg | 2.7 cents
Vena CBD — subscription | same | $29.96 | 1,500mg | 2.0 cents

At list price, Koi's CBD costs roughly two and a half times what Vena's does per milligram, and about 45% more than Aspen Green's — a brand that carries USDA organic certification Koi does not claim. Only with a 40% sitewide discount applied does Koi reach parity with Aspen Green's everyday price, and it still does not approach Vena's. Whatever you are paying for here, it is not value per milligram.

Note what the promotional pattern is telling you. When we checked, the site was running "Save 40% On All Products" under a code reading STOCKUP40, layered on top of a 20% subscription discount and a 15% first-order offer — while the cannabinoid catalogue pages we retrieved showed items out of stock. We cannot say with certainty whether that reflects genuine depletion or a page-rendering issue on our end, and we are not going to over-read it. But a deep sitewide discount is worth thinking about carefully when it lands three months before a change in the law that affects most of the range.

What Koi Does Well

We have been heavily critical, and a fair review has to set out the other side properly. The return policy is one of the most generous in hemp, and considerably better than most brands we have reviewed:

Returns within 90 days of purchase: 100% refund.
Between 90 and 150 days: 50% refund.
After 150 days: no refund.
The product must be at least 50% full to qualify.
The site separately advertises a 30-Day Money Back Guarantee, which is a different and shorter figure than the tiered policy — worth clarifying before you rely on either.

Koi also publishes batch-specific certificates of analysis searchable by the batch number on the product, and states third-party lab testing for potency and purity. That is the right structure and it is what we ask of every brand in this category. It does not, however, address the FDA's finding — that letter was not about whether the delta-8 content was accurately measured. It was about whether delta-8 belongs in food at all.

Ninety days at a full refund, on a product you may have used half of, is materially better than what we found at Vena, whose comparable guarantee applies only to first-time customers, and better than most retailers in this batch. If you buy Koi's plain CBD and it does not suit you, you have a genuine and unusually long route to your money back. That is a real point in the company's favour and we would not want it buried.

How It Compares

Against the hemp brands we have reviewed on this site.

Brand | Cost per mg CBD | FDA warning letter | Notable credential | Return policy
Koi CBD | 7.0 cents | Yes — July 18, 2023, adulterated delta-8 gummies | Batch COAs | 90 days at 100%, tiered to 150 days
Vena CBD | 2.7 cents (2.0 on subscription) | None found | Full contaminant panel testing via Medterra | 30 days, first-time customers only
Aspen Green | 4.8 cents | None found | USDA organic certification | 30 days, accepts opened product
Five CBD | see our review | None found | Medterra manufacturing | see our review

One caveat that applies to every brand in this table, Koi included: the November 12, 2026 redefinition puts every full-spectrum and intoxicating product above a 0.4mg total THC per container limit. That is an industry-wide problem, bills to delay it are pending, and no brand here is exempt. It is a reason not to prepay for a year of anything, not a reason to prefer one over another.

Read that table honestly and Koi loses on the two things that matter most in this category. It is the most expensive per milligram, and it is the only one carrying a federal enforcement letter. Its genuine advantage — the 90-day full-refund window — is real but is not the axis most people should be choosing on. If you want cheap CBD, Vena. If you want a verifiable credential, Aspen Green. If you want a long return window and are content with the rest, Koi.

Pros and Cons

After checking the catalogue, pricing, policies and regulatory record. What's good:

A 90-day 100% refund window, tiered to 50% out to 150 days, on product up to half used — among the most generous in hemp.
Batch-specific certificates of analysis, searchable by the batch number on the product.
Third-party lab testing stated for potency and purity.
A long-established brand with a wide range across CBD formats — tinctures, gummies, topicals, vapes and pet products.
US-only shipping with clear geographic limits, including territories and APO/FPO/DPO.
Meaningful discounting — a 20% subscription rate, 15% first-order offer, and sitewide promotions that materially cut the list price.
A broad-spectrum (THC-free) line, which is the part of the catalogue unaffected by the scheduling and redefinition issues.

What to watch out for: (1) An FDA warning letter dated July 18, 2023 finding Koi's Delta 8 Gummies adulterated for containing an unsafe food additive. (2) THC-O is Schedule I per the DEA, and HHC was placed in Schedule I effective May 4, 2026 — both appear in the affiliate materials for this brand. (3) Delta-8 carries documented harm data: 104 FDA adverse event reports, 2,362 poison-centre exposures, 18% hospitalisation including paediatric ICU admissions. (4) THC-O combustion produces ketene, the lung toxicant implicated in the EVALI outbreak. (5) 7.0 cents per milligram — the most expensive CBD in our comparison, roughly 2.5× Vena. (6) The November 12, 2026 redefinition catches effectively every intoxicating product in the range. (7) Every product will fail a drug test. (8) The site advertises a 30-day guarantee alongside a 90/150-day tiered policy — two different figures.

Who Should Buy, and What to Avoid Entirely

Do not buy, at all: HHC and THC-O products, wherever you find them. The DEA's position is that both are Schedule I controlled substances — THC-O because it does not occur naturally in the plant, HHC by explicit scheduling effective May 4, 2026. The affiliate materials for this brand still list them. The legal exposure for possessing a controlled substance is yours. Anyone who is drug tested for employment, a professional licence, custody or probation. Every THC isomer here triggers a standard panel. Anyone with children in the home who is not prepared to store these products locked away like medication. Reasonable, with eyes open: An adult in a state where these products are legal, who wants Koi's plain CBD or broad-spectrum line — the part of the catalogue with none of the above problems — and who values the 90-day full-refund window enough to pay a premium per milligram for it. Better options exist for most people: If your goal is CBD, Vena is roughly two and a half times cheaper per milligram and we found no enforcement record against it. If you want a verifiable third-party credential, Aspen Green holds USDA organic certification and also has no warning letter. Both are easier recommendations than this one. Check your state before anything else. Delta-8 is banned or restricted in a significant number of states, and a retailer's willingness to ship is not a legal opinion — as we found reviewing Kingdom Kratom, do-not-ship lists in this industry are frequently out of date with the law.

If you take any of these products and something goes wrong — severe anxiety, vomiting, confusion, a racing heart, or loss of consciousness in yourself or anyone else — that is an emergency room visit, not something to sleep off. For a suspected ingestion by a child, call Poison Control on 1-800-222-1222 immediately. Tell clinicians exactly what was taken; delta-8 and its relatives do not behave identically to cannabis and the information genuinely helps.

Frequently Asked Questions

Is Koi CBD legit? It is a real, established California hemp company with batch-specific lab results and a generous return policy. But it received an FDA warning letter on July 18, 2023 finding two of its products adulterated, which is a serious mark on its record and the only one we have found across the hemp brands reviewed on this site. What did the FDA say about Koi? Following an inspection of Koi's Norwalk, California facility on December 12–15, 2022, the FDA issued warning letter #651252 on July 18, 2023, determining that Koi brand "Delta 8 Gummies" and Hemp Living brand "Pot Rocks" are adulterated because they contain an unsafe food additive — no regulation authorises delta-8 THC in conventional food, and the FDA said it knew of no basis to consider it generally recognised as safe. Is delta-8 THC legal? Federally it has not been scheduled on the same basis as THC-O, but it is banned or restricted in a substantial number of states, it is the subject of the FDA action above, and from November 12, 2026 it falls outside the new federal hemp definition in any product exceeding 0.4mg total THC per container. Check your own state. Is HHC legal? No. The DEA listed HHC in Schedule I with its own drug code, effective May 4, 2026, on the basis that tetrahydrocannabinols made by chemical conversion are not "tetrahydrocannabinols in hemp" even when hemp-derived. Is THC-O legal? No. The DEA has stated that delta-8 and delta-9 THC-O acetate do not meet the definition of hemp because they do not occur naturally in the plant, making them Schedule I controlled substances. Separately, research published in January 2023 found that burning THC-O produces ketene, a potent lung toxicant linked to the EVALI vaping injury outbreak. How dangerous is delta-8? The documented record: 104 FDA adverse event reports and 2,362 poison-centre exposures in roughly the same period, with hallucinations, vomiting, tremor, confusion and loss of consciousness among the effects. 18% of cases required hospitalisation, including children admitted to intensive care. How much does Koi CBD cost? The Naturals Broad Spectrum tincture is $69.99 for 1,000mg in 30ml — 7.0 cents per milligram, the most expensive in our comparison. Sitewide promotions of up to 40%, a 20% subscription discount and a 15% first-order offer were running when we checked. What is Koi's return policy? 100% refund within 90 days, 50% between 90 and 150 days, and none after 150 days, with the product at least 50% full. The site separately advertises a 30-Day Money Back Guarantee — two different figures, so confirm which applies before you buy. Will Koi products make me fail a drug test? Any product containing delta-8, delta-9, THC-P, THCA or HHC will. Standard tests detect THC metabolites and do not distinguish delta-8 from delta-9. Broad-spectrum CBD is marketed as THC-free but no CBD product can be guaranteed to be undetectable. Does Koi ship internationally? No — United States only, including US territories and APO/FPO/DPO addresses. Is CBD approved by the FDA? No. Apart from one prescription epilepsy medication, CBD is not approved as a dietary supplement or food additive, and no CBD product is approved to treat any condition.

The Bottom Line

Our rating: 5.0 / 10 — Caution Advised. Koi does some things properly. It publishes batch-specific certificates of analysis you can look up by the code on the bottle, states third-party testing for potency and purity, ships only within the United States, and offers a 90-day 100% refund on product up to half used — tiered to 50% out to 150 days. That return policy is among the most generous in hemp and is genuinely better than most of the brands we have reviewed. We want that on the record. Everything else points the other way. The FDA issued this company a warning letter on July 18, 2023, after inspecting its Norwalk facility, finding that Koi brand "Delta 8 Gummies" and Hemp Living brand "Pot Rocks" were adulterated because they contain an unsafe food additive. No regulation authorises delta-8 THC in food and the agency said it knew of no basis to call it generally recognised as safe. Across every hemp brand we have reviewed on this site, this is the only federal enforcement letter we have found — and in an industry where nearly every quality claim is self-reported, that record is one of the few hard signals a buyer has. Much of the rest of the catalogue has been ruled out from under it. The DEA holds that THC-O acetate is not hemp and is Schedule I, and it placed HHC in Schedule I effective May 4, 2026 — on reasoning that reaches any tetrahydrocannabinol made by chemical conversion. The affiliate materials prepared for this brand still point at HHC and THC-O landing pages. We have not linked to them and we would not buy them. And on November 12, 2026, the new 0.4mg total THC per container definition catches effectively every intoxicating product that remains. The safety data on the product the FDA named is not reassuring either: 104 FDA adverse event reports, 2,362 poison-centre exposures, and 18% of cases requiring hospitalisation — including children admitted to intensive care. These products are sold as sweets, and children cannot tell the difference. Then there is simple value. At 7.0 cents per milligram, Koi's CBD is the most expensive we have priced — roughly two and a half times Vena and about 45% more than Aspen Green, a brand that holds USDA organic certification and has no warning letter. Only a 40% sitewide discount brings it to parity with Aspen Green's ordinary price. Our recommendation: if you want CBD, buy it somewhere else — the cheaper options in our comparison have better records and better prices, and there is no reason to pay a premium to a brand carrying a federal adulteration finding. If you specifically want Koi's plain broad-spectrum CBD and value the 90-day refund, that part of the range is untouched by any of the above and is a defensible purchase. Avoid the HHC and THC-O products entirely — the DEA says they are controlled substances and the exposure is yours, not the retailer's. Avoid all of it if you are drug tested, and lock any of it away if there are children in your home. We are not healthcare professionals and this is not medical or legal advice. The FDA has not approved CBD as a dietary supplement or to treat any condition. Cannabinoid law differs by state and is changing quickly — verify your own current state law before purchasing. For a suspected ingestion, call Poison Control on 1-800-222-1222; for severe symptoms, seek emergency care. Verify current pricing and terms directly with the retailer; we checked on August 7, 2026. This is an affiliate marketing website; see our [disclosure](/disclosure).

Sources & References

Medical Disclaimer

This article is for informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare provider before making decisions about your health or medications. Individual experiences may vary.

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