HBOT Drug Interactions: What Medications to Avoid Before Treatment

Most patients on routine medications can receive HBOT without problems. But a small number of drugs create serious interactions with high-pressure oxygen. Some of those interactions have been fatal.

Disclosing every medication — including chemotherapy history — to your hyperbaric physician before starting treatment isn’t optional. It’s the most important step in pre-treatment evaluation.

Absolute Contraindications: Don’t Combine These with HBOT

Disulfiram (Antabuse) is used to treat alcohol use disorder. It works by blocking an enzyme in oxygen metabolism. That same mechanism creates pulmonary toxicity risk under the high-oxygen conditions of HBOT. Patients taking disulfiram should not receive HBOT until the drug is discontinued and fully cleared — discuss the timeline with the prescribing physician.

Bleomycin is a chemotherapy drug used for several cancers including Hodgkin lymphoma and testicular cancer. It causes a specific pattern of lung damage that becomes dramatically worse with exposure to high oxygen concentrations. Cases of fatal pulmonary oxygen toxicity have occurred in patients treated with HBOT who had prior bleomycin exposure. This risk persists years after chemotherapy ends — bleomycin-damaged lung tissue doesn’t recover its normal oxygen tolerance.

If you’ve ever received bleomycin, tell the hyperbaric physician before they schedule your first session. This is non-negotiable.

Doxorubicin (Adriamycin) is another chemotherapy agent with cardiac and pulmonary toxicity that can be potentiated by high oxygen. The interaction risk with HBOT is well-documented in the hyperbaric medicine literature. Weaver (2014) and UHMS indications guidance both identify doxorubicin as a serious contraindication.

Cisplatin has evidence suggesting enhanced organ toxicity when combined with HBOT. The data is less definitive than for bleomycin and doxorubicin, but the interaction is recognized in UHMS guidance. Patients with cisplatin history need physician review before proceeding.

Relative Contraindications: Careful but Not Excluded

Corticosteroids like prednisone are commonly used alongside HBOT treatment courses, particularly for radiation injury and wound conditions. Some older literature raised concern about seizure risk with corticosteroids during HBOT, but the evidence is mixed and most patients continue necessary corticosteroids during treatment. Your hyperbaric physician will weigh the risk-benefit for your specific situation.

Some anticonvulsant medications affect seizure threshold. Since oxygen toxicity seizures are a known (though rare) risk of HBOT, the interaction between seizure threshold medications and HBOT warrants specific review. Tell your physician about any neurological medication.

Medications That Are Generally Fine

Most people worry about common medications unnecessarily. Antibiotics have no significant interaction with HBOT — this comes up frequently, and the concern isn’t warranted for most antibiotic classes.

Blood thinners and anticoagulants don’t have a direct HBOT interaction, though your care team will note them for procedural reasons.

Antihypertensive medications generally don’t interfere with treatment. Blood pressure monitoring during sessions is standard practice at most facilities.

Insulin and blood glucose medications deserve specific attention not because of a dangerous interaction, but because HBOT can lower blood glucose during and after treatment. The timing of insulin doses and meals relative to your session may need adjustment. Discuss this with your hyperbaric physician before your first session. Blood glucose is typically monitored before and after sessions in diabetic patients.

The Chemotherapy History Problem

Many HBOT referrals are for wound complications in cancer survivors. A patient finishing radiation treatment for head and neck cancer may develop osteoradionecrosis or tissue necrosis years later — both conditions where HBOT is beneficial.

But cancer survivors often received chemotherapy that included bleomycin or doxorubicin. Those exposures may have been years or decades earlier. Patients don’t always remember what they received or think to mention it.

Before starting HBOT, get a complete medication history from your oncologist if you’re a cancer survivor. Don’t rely on memory. The treating oncology team can provide a treatment summary.

What to Do Before Starting Treatment

Bring a complete medication list to your pre-HBOT evaluation. Include everything — prescriptions, over-the-counter medications, supplements, and any past chemotherapy. Herbal supplements like St. John’s Wort are worth disclosing because they can affect drug metabolism.

Never stop or change a medication specifically for HBOT without consulting the prescribing physician. A care team decision about whether to pause a medication involves both the prescribing doctor and the hyperbaric physician together.

FAQ

Can I take my inhaler before HBOT if I have asthma? Most patients with well-controlled asthma receive HBOT without issue. Uncontrolled asthma or significant air trapping can be a contraindication. Discuss your current asthma control with the hyperbaric physician. Bring your inhaler to every session.

Do vitamins or supplements interact with HBOT? Most standard vitamins don’t create clinical interactions. Vitamin E has some theoretical antioxidant effects that might theoretically modify HBOT’s oxidative mechanisms, but clinical impact is unclear. Disclose all supplements regardless.

How far in advance should I stop disulfiram before HBOT? This is a clinical decision for the prescribing physician and hyperbaric physician to make together. It depends on dosing and clearance rates. Don’t make this decision independently.

Medical Disclaimer: This page provides general information about HBOT medication interactions. It is not medical advice. Never stop or change a medication without consulting a qualified physician. Always disclose your complete medication history to the hyperbaric medicine team before treatment begins.

Related guides: HBOT Contraindications | HBOT Side Effects | What to Expect at Your First Session