Oxygen is fundamental to human life, making up about 21% of the air we breathe. The process for purchasing oxygen depends on whether the need is for regulated medical treatment or general consumer use. Medical oxygen is classified as a drug and a medical device by regulatory bodies, requiring strict protocols for acquisition. Supplemental oxygen marketed for wellness or recreation is treated as a non-regulated consumer product.
Obtaining Oxygen for Prescribed Medical Use
Acquiring oxygen for a diagnosed respiratory condition begins with a formal medical assessment. A physician must determine a clinical need based on demonstrated low blood oxygen levels, often verified through an arterial blood gas study or pulse oximetry. This testing establishes a diagnosis of hypoxemia, which is the prerequisite for receiving supplemental oxygen therapy.
The physician then issues a detailed prescription, frequently referred to as a Durable Medical Equipment (DME) script. This script specifies the required flow rate, duration, and conditions for oxygen use, often detailing different flow settings for rest, activity, and sleep. Without this valid order from a licensed healthcare provider, medical-grade oxygen cannot be dispensed.
Medical oxygen is not typically supplied by standard retail pharmacies. Instead, it is distributed by specialized Durable Medical Equipment (DME) or Home Medical Equipment (HME) providers. These companies deliver the equipment, set it up in the patient’s home, and provide instruction on its safe use.
The cost of prescribed oxygen and necessary equipment is often covered by insurance programs, including Medicare and private health plans. To qualify for coverage, the physician must submit a Certificate of Medical Necessity (CMN) to the payer, documenting that the therapy is medically appropriate. Insurance providers typically require the patient to meet specific saturation criteria and may mandate periodic re-testing to confirm the ongoing need. The DME company manages the logistics of refills, maintenance, and compliance monitoring.
Over-the-Counter Options for Supplemental Oxygen
For individuals seeking oxygen for non-medical reasons, such as improved athletic performance or temporary relief at high altitudes, non-prescription options are widely available. These products are sold as supplemental, recreational oxygen and are not intended to treat, cure, or prevent any disease. They are not regulated by the FDA as medical treatments.
These over-the-counter products are primarily sold in lightweight, handheld aluminum canisters containing purified gas, often at about 95% pure oxygen. The volume and flow rate from these canisters are significantly lower than medical-grade equipment. The limited supply is designed for short, intermittent bursts of inhalation rather than continuous therapy.
Consumers can purchase these canisters from various retail locations, including large online marketplaces, fitness centers, and sporting goods stores. Convenience stores, particularly those in high-altitude regions, frequently stock these products for travelers experiencing altitude acclimation issues. Because no prescription is required, the purchase process is identical to buying any other consumer wellness product.
Navigating Oxygen Delivery Systems and Equipment
Once a prescription is secured, patients must choose or be assigned a specific delivery system, which determines the format in which the oxygen is supplied. The two primary types of equipment are oxygen concentrators and high-pressure tanks or cylinders. Each system offers distinct advantages and logistical considerations.
Oxygen concentrators are electrical devices that draw in ambient air, pass it through molecular sieve filters to remove nitrogen, and deliver concentrated oxygen to the user. Concentrators are favored for long-term home use because they provide an unlimited supply of oxygen as long as they have access to power, eliminating the need for frequent deliveries or tank exchanges. They are available as large, stationary home units or smaller, battery-powered portable models designed for mobility.
Alternatively, oxygen tanks are metal cylinders that store a fixed amount of compressed oxygen gas or liquid oxygen. Compressed gas tanks are heavier but offer a reliable, non-electric source of oxygen, making them suitable for emergency use or short trips. Liquid oxygen systems store the gas at extremely cold temperatures, allowing a large volume to be kept in a small, lightweight container, though the liquid will slowly evaporate over time.
Regardless of the primary system, the oxygen is delivered to the patient through accessories like a nasal cannula or a specialized face mask. Regulators must be attached to tanks to control the pressure and flow rate precisely, ensuring the patient receives the exact dose specified in the prescription. Other accessories, such as humidifiers, are sometimes added to moisten the oxygen flow and prevent the drying of nasal passages during extended use.