What to Expect at an EBO2 (EBOO) Session: A Timeline From Clinic Pages and the Studies

EBO2 (also called EBOO) is a clinic procedure in which blood is pumped from one arm, through a device where it meets an oxygen and ozone gas mixture, and back into the other arm for about an hour [1][2]. A first visit has four stages: an intake with screening, sometimes on an earlier day; preparation, mostly hydration and a meal; the hour on the circuit; and a short check before you leave. Ozone therapy is not FDA-approved for any condition [3].

This guide builds that timeline from two kinds of source. One is what clinic pages say: as of October 4, 2026, we could read the EBO2 pages of 174 of the 177 clinics in our directory, and we counted their statements from the saved pages. The other is the published papers, which describe the procedure but say almost nothing about the patient’s day. A few chains repeat one page across locations, and each location counts once. The guide ends with questions to ask at intake.

The timeline at a glance

Before you book: the intake

Of the 174 pages we could read, 132 describe what happens before a first session. We recorded one statement per clinic, so the counts below are a floor. Of those 132 statements, 120 describe a consultation, evaluation or screening, 45 mention a review of health history, 35 mention lab work or other testing, and nine mention medications. Five of those statements state a price for the consultation, from $125 to $450, and a free consultation is stated in one of the 132. Anywhere on the pages we saved, 10 clinics list a fee for a consultation, evaluation, or first visit, from $50 to $600, as our cost guide itemizes.

Labs. Anywhere on the saved pages, 31 of 174 mention G6PD, an enzyme whose deficiency clinics treat as a reason not to proceed; 18 describe a G6PD test before treatment, and the rest list the deficiency only as a reason to decline. In the intake statements alone, 11 name a G6PD test. Nine pages, two of them locations of one practice, name the same three tests: a complete blood count, a metabolic panel and G6PD. One clinic says results from the past three months may let it waive repeat testing [7].

Extra steps at some clinics. A few clinics ask for more before an EBO2 session. One requires a previous high-dose IV ozone treatment “to make sure you can tolerate high dose ozone” [8]. Another lists “one well-tolerated IV UVBI session” and “two compliant veins (one in each arm)” among its prerequisites [9]. A third schedules a separate pre-therapy visit “for vein assessment” [10]. At the other end, one clinic says treatment can follow the intake on the same day [11], and four say a clinical check comes before every session, not only the first.

Who you will see. Of the 174 pages, 100 say who supervises or performs sessions. Of those, 57 name no profession, saying only “medical supervision”, “trained professionals” or similar; the rest mention a physician, nurse practitioner, nurse or naturopathic doctor, and at two locations of one practice, chiropractors. The technique’s developers wrote that EBOO “must be performed by technicians specialized in extravascular blood circulation” [1]. Our guide to who should not get EBO2 lists the conditions clinics screen for.

What the papers add. Little. The abstracts of the Siena papers describe no screening protocol, and the California group’s patients were consecutive patients on routine treatment, with “no exclusion criteria” [2].

The day before and the morning of

Water. Of the 174 pages, 42 ask patients to arrive hydrated, and the reasons they give are practical: “Well-hydrated veins make catheter placement easier” [12], and one calls hydrating the day before “essential for accessing the veins” [13]. One asks for 32 to 40 ounces of water in the two hours before the appointment [14].

Food. Thirty-five pages tell patients to eat beforehand, usually a light meal one to two hours ahead. The reason given is blood sugar. One clinic warns against arriving on an empty stomach so blood sugar stays stable through the session [12]; another checks that blood glucose is at least 100 mg/dL at the start “to avoid hypoglycemia” [9].

Alcohol and clothing. Twelve pages ask patients to avoid alcohol beforehand. Several ask for loose or short sleeves, since both arms need a line.

Medicines. The circuit is anticoagulated. The 2023 California paper dripped in a liter of saline holding 15,000 units of heparin, of which about 300 mL reached the patient during the hour, with more used to prime and flush the lines before and after [2]. Anyone taking a blood thinner or a supplement that affects bleeding has reason to raise it at intake; only nine of the intake statements we read mention medications. Our guide to blood thinners and other medicines lists questions for the prescribing doctor and for the clinic.

No paper we read tested whether any of this preparation changes how a session goes.

Arrival and setup

Check-in can include a short review and vital signs: anywhere on the saved pages, 16 mention vital signs, 15 of them as taken or monitored at a session, and one lists “an intake review, consent, vitals, and a pre-procedure evaluation” before every session [15]. Then come two lines, one in each arm. The published descriptions match: blood leaves through one vein and returns through a vein in the other arm [1]. The California group used a 20-gauge catheter in each arm and kept to that size, although larger catheters allow faster flow, to protect patients’ veins over repeated sessions [2].

Setup is not counted in most stated session lengths. One clinic starts its hour only after IV access is established [16]; another plans 75 to 90 minutes in all, “including check-in, preparation, and a brief post-treatment monitoring period” [12].

The hour on the circuit

How long. Of the 174 pages, 101 state how long a session takes. The figures run from 25 to 120 minutes, with a median of about 75, and 65 fall between 60 and 89 minutes (taking the midpoint where a page gives a range). The chart under “From our data” shows the spread. Ten pages say the whole visit takes about two hours, including consultation and monitoring, and eight of them are locations of one chain [17]. One clinic starts at 25 minutes and works up to 60 “as tolerated” [18].

The papers are more uniform. Siena’s standard technique was one hour, repeated 14 times over seven weeks [4], and the California treatments ran “exactly 1 hour” [2]. In the developers’ 1999 sheep experiments the gas exchanger worked less well after 50 minutes because it clogged with cells (Bocci 1999) [19]. By 2001 they reported more biocompatible oxygenators that could treat up to 5 liters in about an hour [20].

Who watches what. One clinic says vitals, blood glucose and oxygenation are monitored in real time throughout [15]. The Siena group monitored blood chemistry: after a session it measured a 4- to 5-fold rise in a marker of lipid oxidation and a fall in plasma protein thiols, and proposed those tests for routine monitoring [4]. The California paper measured the gas going in and out every 15 minutes, which tells you how much ozone the circuit used, not how the patient was doing [2]. Monitoring matters when something goes wrong: in 2025 a New South Wales commission found that an ozone practitioner did not check a patient’s vital signs when she reacted to treatment, in a clinic where it also found he obtained heparin “from an unknown source” and “is not authorised to be in possession of, or to administer” it, and that the clinic had no infection control [21]. That order concerned ozone therapy with a UV device, not a documented EBOO circuit.

What it feels like. The papers do not say. One clinic lists chills during the session among the effects patients most commonly report [15].

After the session

Aftercare is the thinnest part of what clinic pages say. Of the 174 pages:

• Twenty-five say normal activities can resume the same day or that there is no downtime; one says the following morning [14].
• Twenty-eight mention tiredness afterward, and thirteen of those attribute it to “detox”. We found no study that tested that explanation.
• Sixteen say to keep drinking water afterward, and seven advise against strenuous exercise for the rest of the day.
• Ten mention bruising or tenderness where the lines went in.
• Thirteen describe a check or monitoring period before you leave.

One page tells patients that many “feel tired after their EBO2” and to “take rest as you need” [22]. The papers record few problems: none in 210 treatments in the Siena trial [5] and none in at least 400 California sessions [2]. In a 2025 case report from New York, the patient said she felt more tired after her second series of three treatments than after the first, and her care turned to her anemia [6]. For symptoms that warrant a call to the clinic or urgent care, see side effects and safety.

The course

Of the 174 pages, 69 state a recommended course or schedule. In Siena the standard cycle was 14 sessions over seven weeks [4]. In the 2025 case report, three treatments ran over two weeks, on February 13, 18 and 27, because the clinic’s protocol assumed that three treatments of about 2 liters would process “nearly all of the patient’s blood” [6]. A clinic that offers the procedure calls that kind of reasoning “mostly a marketing gimmick” and says dose is measured in micrograms per milliliter, not liters [7]. What clinics recommend and sell is in how many sessions, and the session cost planner totals a course.

Questions to ask at intake

Each question below comes from a gap in what clinic pages say.

1. Which device and filter do you use: a gas exchanger built for ozone, or a dialysis filter? Who makes it? See what EBO2 is for why this differs between clinics, and EBO2 devices and FDA status for how to look a device up.
2. What ozone concentration, blood flow and session length will you use? Only seven of the 174 pages we read state a concentration.
3. Which anticoagulant do you use, and how much? What do you need to know about my medicines and supplements?
4. Which labs do you need before the first session, how recent must they be, and is a G6PD test among them? Do they cost extra?
5. Who places the lines, who stays in the room for the whole session, and what are their licenses?
6. What do you monitor during the session, and what do you do if I feel faint, short of breath or unwell?
7. How long is the whole visit, not just the time on the circuit?
8. What does the quoted price include: consultation, labs, add-ons? See what else EBO2 clinics sell.
9. What should I do afterward, what is normal, and whom do I call if something is not?

A printable list built from our contraindications guide is at questions for your doctor.

What we could not verify

• What happens in practice. Clinic pages describe what clinics say they do; we did not observe sessions.
• Whether any preparation advice matters. No paper we read tested hydration, meals or fasting before EBOO.
• The “detox” explanation for tiredness after a session. We found no study of it.
• Aftercare and complication rates outside the practitioners’ own series. The papers report few problems, but no independent monitoring or registry.
• Whether stated session lengths include setup. Most pages do not say.
• The full Siena protocols. We read the abstracts only, which do not describe screening, preparation or aftercare.
• The dates in the 2025 case report: it places a check-in on April 14, 2025, “about a month after” the first series, and the second series on April 1, 10 and 29 of the same year [6].

How this guide was made

This guide draws on 22 sources: papers read through PubMed Central and Europe PMC, regulatory documents read on the issuing bodies’ sites, and clinic pages saved by our research pass. The clinic counts come from our dataset of 177 clinics, read between September 28, 2026 and October 4, 2026; we counted preparation, aftercare, monitoring and supervision statements from the saved pages, checked every count against them, and kept the list of pages behind each one. Drafting used AI tools. A human editor has not yet checked this guide claim by claim against its sources, and no clinical reviewer has signed off yet.