HBOT and Your Eyes: Contacts, Dryness, and the "Myopic Shift" Explained

So, you’re about to dive into the world of mild Hyperbaric Oxygen Therapy (HBOT). Whether you're biohacking your way to better sleep, speeding up muscle recovery, or just looking for a serious wellness boost, getting into the hyperbaric chamber is an amazing experience. But as you're getting ready to zip up, a thought crosses your mind: "Wait, do my eyes feel weird in there? Should I take out my contacts?"

It’s a super common question. While hyperbaric therapy is incredibly comfortable, your body—including your eyes—does experience some fascinating physiological changes under pressure. Here is everything you need to know about keeping your eyes happy during your session.

The Golden Rule for Contacts: Soft is Safe, Hard is a Halt

Let’s cut right to the chase regarding your contact lenses. It all boils down to the material:

• Soft Lenses = Good to Go: If you wear standard daily or monthly soft contacts, you don't need to take them out. Because they are porous and flex with your eye, they won't trap air underneath them as the hyperbaric chamber pressurizes.
• Hard Lenses (RGP) = Take Them Out: If you wear rigid gas-permeable lenses or overnight ortho-k lenses, you absolutely must remove them before your session. Hard lenses don't bend. As pressure changes, tiny air bubbles trapped behind the rigid lens can expand, causing serious pain or scratching your cornea. Play it safe and pop them in their case.

What Actually Happens to Your Eyes Under Pressure?

A lot of people worry that high concentrations of oxygen will irritate their eyes. Here's a cool fact: in most modern wellness hyperbaric chambers, your eyes aren't actually absorbing extra oxygen at all!

In standard recovery setups, the chamber itself is filled with compressed room air. You get your oxygen boost by breathing through a comfortable face mask. Because your eyes are just exposed to regular (though compressed) air, they don't experience direct external irritation. Any changes that happen to your eyes actually come from the inside.

The Curious Case of the "Myopic Shift"

For the hardcore biohackers doing long, intense, and highly frequent blocks of hyperbaric sessions, there is a fascinating phenomenon known as the "myopic shift."

As you breathe in oxygen under pressure, your blood becomes supersaturated. This oxygen-rich blood circulates everywhere, including the tiny blood vessels behind your eyes, raising the oxygen levels in your eye fluids. Over many sessions, this internal oxygen boost can actually change the refractive index of the lens inside your eye.

The result? You might temporarily feel like your nearsightedness has gotten a little worse, or oddly enough, if you need reading glasses, you might suddenly find you can read up close without them! Don't panic, though—this shift is completely reversible. Once you finish your routine sessions, your vision will naturally return to its baseline within a few weeks.

How to Prep Your Eyes for the Best Experience

Want to ensure maximum comfort while you recover? Follow these quick tips:

Hyperbaric therapy is all about giving your body the environment it needs to thrive, heal, and optimize. Now that you know exactly how to protect your eyes, you can step into the chamber, put on your mask, and just breathe.