Cytisine for Quitting Smoking: Does It Work and Can You Get It?

There is a quit-smoking pill made from tree seeds that has been sold in Bulgarian pharmacies since 1964, works roughly as well as Chantix, causes less nausea, and sits on the World Health Organization's list of essential medicines. Most people in the US and Western Europe have never heard of it, and as of today Americans still cannot legally buy it.

The drug is cytisine. In June 2026 it came within two days of American approval and then missed, for reasons that had nothing to do with whether it works. Here is what it actually does, how strong the evidence is, and whether it is worth waiting for.

What Cytisine Actually Is

Cytisine comes from the seeds of Laburnum anagyroides, the golden rain tree. Soviet-era researchers noticed the seeds had been used as a tobacco substitute during wartime shortages and worked out why: the molecule looks enough like nicotine to fit the same lock.

That lock is the alpha-4 beta-2 nicotinic acetylcholine receptor, the one nicotine binds to in order to trigger a dopamine release. Cytisine is a partial agonist there. It binds tightly, produces a much weaker signal than nicotine would, and while it is sitting in the receptor, nicotine cannot get in.

Two things follow from that. Withdrawal is blunted, because the receptor is not sitting empty. And if you smoke a cigarette anyway, it does much less for you, because the receptor is already occupied. If that mechanism sounds familiar, it should. It is exactly how varenicline works, the drug sold as Champix and Chantix. Varenicline was in fact developed after researchers went looking at cytisine's structure. The older drug came first.

For more on what nicotine is doing to those receptors in the first place, see the science behind nicotine addiction.

Cytisine or cytisinicline?

Both names refer to the same molecule. Cytisine is what it has been called in Europe for sixty years. Cytisinicline is the standardised international name adopted for the version Achieve Life Sciences has taken through US clinical trials. When you see the two used in the same paragraph, nobody is comparing two drugs.

How Well Does It Work?

Better than most people expect from something this old and this cheap.

The Cochrane review, which pools the trial evidence rather than relying on any single study, found cytisine helps more people quit than placebo with a relative risk of 1.30 (95% confidence interval 1.15 to 1.47). That is graded moderate certainty, which in Cochrane terms means the finding is unlikely to be overturned by the next study.

The two large modern trials, ORCA-2 and ORCA-3, both ran in the US against placebo. The numbers were consistent across both:

Trial and arm	Quit rate	Placebo
ORCA-2, 12 weeks of treatment	32.6%	7.0%
ORCA-3, 12 weeks of treatment	30.3%	9.4%
ORCA-2, still quit at 24 weeks	21.1%	4.8%
ORCA-3, still quit at 24 weeks	20.5%	4.2%

Read those bottom two rows carefully, because they are the honest ones. About one in five people who took cytisine for twelve weeks were still not smoking six months later. That is a genuinely good result for a smoking cessation drug. It is also a reminder that four in five were smoking again, which is true of every quit method ever studied.

The trials also found the 12-week course clearly beat the 6-week course. If you end up taking this, the longer schedule is the one with the better numbers behind it.

Against Chantix

One trial has compared them head to head. RAUORA enrolled 679 Māori smokers and their families in New Zealand and randomised them to cytisine or varenicline. At six months, verified continuous abstinence was 12.1% on cytisine against 7.9% on varenicline.

Take that gap with some caution. The trial was designed to show cytisine was not worse, not to prove it was better, and a single trial in one population cannot settle the question. The safer reading is that the two drugs perform in the same range.

The side effect difference was the more striking result. Nausea hit 22.5% of the cytisine group and 39.1% of the varenicline group. Vivid dreams, which is the complaint that pushes a lot of people off Champix, affected 7.2% versus 17.4%. If you have tried varenicline and stopped because of how it made you feel, that gap is the interesting part of this whole article. Our guide to Champix and Chantix side effects covers what you would be comparing it against.

Where it sits among the options

	Cytisine	Varenicline	NRT
Course length	25 days to 12 weeks	12 weeks	8 to 12 weeks
Contains nicotine	No	No	Yes
Main complaint	Stomach upset, awkward dosing	Nausea, vivid dreams	Skin irritation, jaw ache
Prescription needed	Depends on country	Yes	No

If you are weighing up the nicotine-based options instead, our comparison of patches, gum and lozenges breaks those down, and Zyban and bupropion covers the other non-nicotine prescription route.

The Dosing Is the Annoying Part

Nobody mentions this in the headlines. The traditional Tabex schedule is one of the most demanding in medicine:

• Days 1 to 3: one tablet every two hours, six a day
• Days 4 to 12: one every two and a half hours, five a day
• Days 13 to 16: one every three hours, four a day
• Days 17 to 20: one every five hours, three a day
• Days 21 to 25: one or two a day

You are meant to keep smoking for the first five days and then stop completely. Six alarms a day for the first three days is a real barrier, and dosing errors are the most common reason people abandon the course.

The newer schedule used in the ORCA trials is simpler: 3mg three times a day for six or twelve weeks. If cytisinicline reaches US pharmacies, that is the version it will use.

Side Effects and Who Should Not Take It

The complaints are mostly digestive. Nausea, dry mouth, indigestion and stomach ache lead the list, with headache close behind. Most are mild and settle. Cochrane found no evidence of a difference in serious adverse events between cytisine and placebo, with a relative risk of 1.04, though that estimate is graded low certainty because the numbers involved are small.

Sixty years of use across Eastern Europe is not a formal safety database, but it is not nothing either. No serious safety signal has emerged in that time.

Not suitable if: you are pregnant or breastfeeding, have severe atherosclerosis, or have uncontrolled high blood pressure.

Talk to a doctor first if: you have a psychiatric history, heart disease, a history of stroke, a peptic ulcer, an overactive thyroid, diabetes, or reduced kidney or liver function. The Canadian product label flags all of these.

Whatever you take, the underlying withdrawal still happens on its own schedule. Our hour-by-hour withdrawal timeline covers what the first weeks feel like.

Where You Can Actually Get It

This is where it gets frustrating, because the answer depends entirely on which passport you hold.

United Kingdom. Available on prescription since early 2024, distributed by Consilient Health. NICE guidance tells local services in England to offer it as an option alongside the established treatments. A 25-day course runs to roughly £115, and NHS data put the cost per item at £113.59 in 2024/25. It is still the least-used option on the list, with 2,179 items dispensed across England that year.

Canada. Sold as Cravv since 2017, licensed as a natural health product rather than a prescription drug. You can buy it from some pharmacies and health shops without seeing a doctor. Worth knowing that the natural health product route has a lower evidence bar than drug approval, so the regulatory scrutiny behind it is lighter than the UK version.

Central and Eastern Europe. Registered in around 34 countries and sold cheaply for decades, mostly as Tabex. This is where the reputation for being the cheapest cessation medicine comes from, and where the WHO's affordability argument is grounded.

Rest of the EU. Patchy. Cytisine has never gone through a central European Medicines Agency approval, so availability varies by member state and it is absent in many.

United States. Not approved, no legal regulated supply.

The price gap between those markets is worth naming. Cytisine is genuinely cheap where it has been manufactured for sixty years. In newer Western markets it has been priced closer to the drugs it competes with. The WHO added it to the Essential Medicines List in September 2025 largely on the strength of what it could cost in low and middle income countries, not on what a UK prescription currently costs.

What Happened With the FDA in June 2026

The FDA accepted Achieve Life Sciences' application in September 2025 and set a decision date of 20 June 2026. On 22 June the company announced it had received a Complete Response Letter, which is the FDA's way of saying no for now.

The reasons matter. The FDA identified no deficiencies regarding the clinical efficacy or safety of cytisinicline. What it flagged were manufacturing inspection findings at a third-party facility, which had picked up a general compliance classification unrelated to this drug, and product labelling that had not been finalised by the deadline.

Achieve has since moved manufacturing to Adare Pharma Solutions, completed the technology transfer and made engineering batches. It plans to resubmit in the final quarter of 2026, with approval possible in the first half of 2027 and a launch after that.

So the drug is not in trouble. The paperwork behind one factory was. But a plausible 2027 approval date, from a company that has already missed one, is not a date to plan your health around.

Does It Work for Vaping?

Early signs say yes, and this is the only prescription drug with a trial specifically in people who vape rather than smoke.

ORCA-V1 randomised 160 adults who vaped nicotine and did not smoke. During weeks 9 to 12, 31.8% of the cytisinicline group had stopped vaping against 15.1% on placebo, which works out at about 2.6 times the odds of quitting. The results were published in JAMA Internal Medicine in May 2024.

That is a phase 2 trial, so it is promising rather than settled, and a larger study is needed. In the meantime, our complete guide to quitting vaping covers the approaches available now.

Should You Wait for It?

No.

If you are in the UK or Canada, cytisine is a real option worth raising with a doctor or pharmacist today, particularly if varenicline's side effects have ended a previous attempt.

If you are in the US, the honest position is that the earliest realistic arrival is sometime in 2027, and regulatory timelines slip. Deciding to quit "when the new pill comes out" is the same decision as deciding not to quit now, dressed up as a plan. The methods available today are the ones that will determine whether you are still smoking next year.

It is also worth keeping the scale of the benefit in perspective. The best cessation drugs move a quit attempt from roughly one-in-twenty odds to roughly one-in-five. That is a large relative improvement and still means most attempts fail. What decides the outcome is more often what you do in the first three days and what you have in place for the moments the drug is not designed to touch: the routine, the triggers, the specific times of day your hands expect something. See cold turkey versus gradual reduction for how the non-drug decisions stack up.

The Bottom Line

Cytisine is a sixty-year-old drug with modern trial evidence behind it. It performs in the same range as Chantix with noticeably less nausea and fewer vivid dreams, it costs a fraction of the alternatives in the countries that have made it longest, and the WHO now lists it as an essential medicine.

Its problems are logistical rather than pharmacological. The traditional dosing schedule asks a lot of you. Availability depends on where you live. And in the US it is stuck behind a factory inspection rather than a scientific question, with a resubmission due late in 2026.

If you can get it, it belongs on the shortlist. If you cannot, do not put your quit date on hold waiting for it.