CO₂ Gas Injections — a Treatment You Will Not Find Elsewhere
Mariánské Lázně (Marienbad) has a treatment most people have never heard of, and yet it is characteristic of the spa here. CO₂ gas injections use natural carbon dioxide from the Maria Spring — a gas so pure that physicians apply it in small amounts directly under the skin. It is one of the three forms of CO₂ therapy offered in Mariánské Lázně alongside carbonic baths and dry gas baths.
This article describes what gas injections are, how they are given, when the spa physician includes them in the treatment plan and what review papers say about subcutaneous CO₂ ("carboxytherapy" in the specialist literature). It does not replace medical advice: whether the treatment is suitable for you is decided by the spa physician at the initial examination.
What the Maria Spring Is and Why It Is So Exceptional
The Maria Spring (Mariin pramen, Marienquelle) is a natural source of carbon dioxide that rises in the centre of Mariánské Lázně. Unlike the ordinary mineral springs, which are drunk, the Maria Spring serves exclusively for therapeutic purposes. Its gas, known as Maria's gas, is of volcanic origin and has a CO₂ content of 99.7% — a value comparable to medical-grade gas, yet entirely natural in origin. It is this raw material that gave rise to three local treatments: carbonic baths, dry gas baths and gas injections.
How CO₂ Gas Injections Are Given
The treatment is simple. A physician or trained nurse applies a small amount of natural CO₂ under the skin with a fine needle — most often around the large joints, along the spine or on the lower limbs. The sites and their number are chosen by the physician according to the diagnosis.
The Course of One Application
- Preparation: the injection site is cleaned; the treatment is carried out sitting or lying down
- Application: several punctures with a very fine needle, a small amount of gas into each site
- Sensation during application: mild pressure or a "bubbling" under the skin that subsides within moments
- After the treatment: the gas is absorbed under the skin and the patient can continue with the daily programme
The needle is comparable to an insulin needle, so the puncture itself is uncomfortable rather than painful. Transient redness, slight pressure, a crackling sensation (crepitus) or a small bruise at the injection site are described in a review of 27 carboxytherapy studies as mild and transient adverse effects (Ahramiyanpour et al., 2022, J Cosmet Dermatol).
What Happens in the Body: the Mechanism Described in the Literature
Carbon dioxide is a natural part of metabolism and the body can process it quickly. When a small amount gets under the skin, specialist reviews describe two consecutive processes:
- Local dilation of blood vessels. CO₂ relaxes the smooth muscle of the small vessels nearby, so local blood flow increases. The same mechanism underlies the effect of carbonic baths, where it is well measured (Pagourelias et al., 2011, Int J Biometeorol).
- The Bohr effect. A higher concentration of CO₂ in the tissue makes it easier for haemoglobin to release oxygen. A scoping review of 22 papers on CO₂ therapy concludes that CO₂ given subcutaneously, transcutaneously or in a bath improves local blood flow and oxygenation, dampens the inflammatory response and, in the samples described, speeds the healing of chronic wounds (Prazeres et al., 2025, Biomedicines). The authors point out that the methods used differ considerably between studies.
These are descriptions of the mechanism and observations from reviews, not a promise of a specific outcome for a specific diagnosis. How the treatment affects you is assessed by the spa physician during your stay.
When the Physician Includes Gas Injections
Gas injections are not a separate item in the indication list. They are treatments the spa physician adds to the treatment plan for the diagnosis with which the patient arrives. In Mariánské Lázně, on the basis of long-standing spa practice, they are used mainly:
- locally for musculoskeletal complaints — around painful joints and along the spine, usually in combination with baths, peloids and remedial exercise;
- for circulatory disorders of the lower limbs — in patients from indication group II, for example with disease of the limb arteries (II/4) or functional disorders of the peripheral vessels (II/5);
- in the after-treatment of chronic wounds and slow-healing scars — as a complement to the care led by the treating doctor.
The exact list of diagnoses, type of care and length of covered stay can be found on the page indications and contraindications. The inclusion of gas injections in the treatment plan, their number and the sites of application are decided by the spa physician after the initial examination.
Gas Injections versus Dry Carbonic Baths
Both treatments use the same natural CO₂ from the Maria Spring, but they differ in the method of delivery.
In a dry gas bath the patient lies in a sealed bag filled with the gas, which is absorbed through the skin of the whole body. It is used where the aim is an overall effect on blood flow and the circulatory system.
Gas injections, by contrast, target a specific area: the physician chooses the site of application according to the diagnosis — a painful joint, an area with impaired blood flow or a post-operative scar. In practice the two methods are often combined, and the spa physician draws up an individual plan according to the patient's needs.
The History of Gas Injections in Mariánské Lázně
The therapeutic use of natural CO₂ in Mariánské Lázně dates back to the 19th century, when spa physicians began with carbonic baths. Subcutaneous application of the gas developed in the 20th century and gradually became a standard part of treatment programmes in Mariánské Lázně and other Czech spas. Mariánské Lázně retains a special position thanks to its own natural source of gas.
Practical Information
How Many Applications Are Needed
The number of applications and their frequency are determined by the spa physician according to the diagnosis and how the treatment proceeds; as a rule they are repeated several times a week throughout the stay. The length of stay is governed not by the treatment but by the item of the indication list with which you arrive: for disease of the limb arteries (II/4), for example, the basic stay is 21 days in both comprehensive and contributory care and a repeat stay is 21 days (14 in justified cases). Self-paying guests choose the length in consultation with the spa physician.
Where the Treatment Is Carried Out
CO₂ gas injections are available at the Ensana spa hotels in Mariánské Lázně, where they are prescribed by the spa physician after the initial examination. The treatment is part of comprehensive and contributory spa stays as well as self-paid treatment programmes.
Coverage by Health Insurance
For guests insured in the Czech Republic, comprehensive spa care covers treatment, standard accommodation and meals, contributory care only the treatment; the treatments prescribed by the spa physician, including gas injections, are part of the covered treatment in both cases. Details of the coverage system can be found in the spa treatment insurance guide.
Contraindications
The treatment is not carried out in the presence of acute inflammation or skin disease at the application site, uncompensated heart failure, serious blood clotting disorders or during pregnancy. The general contraindications to spa treatment also apply. Suitability is decided by the spa physician at the initial examination.
A Treatment Worth the Journey
CO₂ gas injections are one of the reasons Mariánské Lázně differs from other spa destinations: a natural healing resource that occurs nowhere else in such purity, and decades of experience with its subcutaneous application. If you are arriving with musculoskeletal complaints or a circulatory disorder of the limbs, ask the spa physician whether gas injections belong in your treatment plan.
