What shouldn't you use hydrogen peroxide on?

September 22, 2025 •

4 min read

For decades, hydrogen peroxide has been a go-to first-aid product for cleaning cuts and scrapes, a practice that is now considered outdated and potentially harmful. The chemical's bubbling action, once mistaken for effective sanitization, can cause significant damage to healthy tissue and delay the healing process. This guide will explore what you shouldn't use hydrogen peroxide on, both for your health and around your home.

Quick Summary

Modern medicine advises against using hydrogen peroxide on open wounds, burns, and irritated skin, as it damages healthy cells crucial for healing and can cause irritation. For first aid, mild soap and water are preferred, while safer cleaning agents exist for household surfaces where peroxide can cause corrosion or discoloration.

Key Points

Avoid Open Wounds: Do not use hydrogen peroxide on cuts and scrapes, as it damages healthy cells (fibroblasts) and can delay healing.
Never Apply to Burns: Hydrogen peroxide can cause further tissue damage and irritation on burns; use cool water and a sterile dressing instead.
Steer Clear of Sensitive Skin: Using it on acne or irritated skin is harsh and can worsen inflammation and redness.
Do Not Ingest: Drinking hydrogen peroxide, even diluted, is extremely dangerous and can cause severe internal damage.
Protect Household Surfaces: Certain materials like wood, some metals (copper, brass), and electronics can be corroded or discolored by hydrogen peroxide.
Choose Modern Alternatives: For first aid, mild soap, water, and petroleum jelly are safer and more effective for wound care.

The Surprising Truth About a Household Staple

Many of us grew up with a bottle of hydrogen peroxide in our medicine cabinets, taught to pour it on every new scrape or cut. The fizzing action seemed like clear proof that it was working its magic, aggressively killing germs. However, the science of wound care has evolved, and the use of hydrogen peroxide for this purpose has fallen out of favor with the medical community. While it remains a useful disinfectant for inanimate objects, understanding its limitations is critical for ensuring proper care and avoiding harm. This article breaks down the specific scenarios where hydrogen peroxide should be avoided and provides safer, more effective alternatives.

Open Wounds and Deep Cuts

Perhaps the most important item on the list of what not to use hydrogen peroxide on is an open wound. While it does kill bacteria, it lacks the ability to differentiate between harmful pathogens and the healthy cells, such as fibroblasts, that are vital for tissue regeneration. When applied to a cut or scrape, the powerful oxidative action indiscriminately destroys these cells, effectively slowing down the body's natural healing process. This prolonged healing time can, ironically, increase the risk of infection. Instead of helping, it can turn a minor injury into a more complicated problem.

Burns

Treating a burn requires a delicate touch, and hydrogen peroxide's corrosive nature makes it a poor choice. The application can cause further tissue damage, irritation, and inflammation, which is the last thing a burn needs. For minor burns, the best course of action is to cool the area with running water and then cover it with a sterile, non-adhesive bandage. Harsh chemicals like hydrogen peroxide or alcohol can significantly exacerbate the injury and should be strictly avoided.

Sensitive Skin and Acne

The idea that hydrogen peroxide can kill acne-causing bacteria has led some to use it as a facial cleanser or spot treatment. This is ill-advised for the same reasons it's not suitable for wounds. It is an irritant that can cause redness, blistering, and further inflammation, especially on sensitive facial skin. Its harsh properties can strip the skin of its natural, protective moisture barrier, leading to dryness and making acne worse. Safe and proven acne treatments, such as benzoyl peroxide or salicylic acid, are much more effective and less damaging options.

Inside the Mouth or for Ingestion

Another common misconception involves using hydrogen peroxide for oral hygiene, such as a mouth rinse, or even worse, ingesting it for unproven health benefits. While diluted solutions are sometimes used in dentistry under professional supervision, using a standard household solution can be dangerous. Swallowing any concentration of hydrogen peroxide can cause severe internal damage, including blistering in the mouth, vomiting, and abdominal distress. Ingesting higher, 'food-grade' concentrations is exceptionally hazardous and can even be deadly.

Certain Household Surfaces

Beyond personal health, there are many cleaning situations where hydrogen peroxide is a bad idea. Its strong oxidizing properties can be damaging to various materials. For instance, it can corrode certain metals like copper, brass, and aluminum, leading to discoloration and rust. It can also strip the protective finish from wooden surfaces, leaving a dull, dry appearance. Additionally, it should be kept away from electronics, as the liquid and corrosive properties can damage sensitive components.

First Aid Alternatives to Hydrogen Peroxide

For most minor cuts and scrapes, a far simpler and safer approach is recommended:

Wash the wound: Use clean, running water and mild soap to gently clean the area, washing away dirt and debris. Avoid scrubbing, which can cause further irritation.
Apply pressure: If there's bleeding, use a clean cloth to apply gentle, firm pressure until the bleeding stops.
Apply ointment: A thin layer of petroleum jelly, such as Vaseline, can help keep the wound moist and protected, creating an ideal healing environment. Some doctors also recommend antibiotic ointments.
Cover the wound: Apply a sterile, non-stick bandage to protect the area from infection and further trauma. Keep it moist, as a moist healing environment is preferable to allowing it to air out.

For more information on proper wound care, consult resources from authoritative health organizations like the National Institutes of Health.

Comparison Table: Appropriate vs. Inappropriate Uses


Situation	Appropriate Use	Inappropriate Use
Minor Wounds	Mild soap and water, saline solution	Hydrogen peroxide
Burns	Cool running water, sterile non-stick bandage	Hydrogen peroxide, ice, butter
Sensitive Skin / Acne	Specialized cleansers (e.g., salicylic acid)	Hydrogen peroxide
Mouth Care	Diluted rinses (under guidance), mouthwashes	Concentrated hydrogen peroxide
Disinfecting Surfaces	Hard surfaces (counters, toilets)	Untreated wood, natural stone, certain metals
Electronics	Isopropyl alcohol, specialized wipes	Hydrogen peroxide
Fabrics	Spot-test on whites for stains	Delicate fabrics (silk, wool), colored fabrics

Conclusion

The bubbling action of hydrogen peroxide, once a comforting sign of disinfection, is now a sign of its outdated and potentially damaging nature for first aid. Modern, evidence-based practices prioritize gentle, effective care that supports the body's natural healing capabilities rather than hindering them. For open wounds, burns, and sensitive skin, ditch the peroxide and opt for simple soap and water, followed by a protective ointment and bandage. For household tasks, be mindful of its corrosive properties and choose surface-specific cleaners. By understanding what you shouldn't use hydrogen peroxide on, you can make smarter, safer choices for both your health and your home.

Frequently Asked Questions

Historically, the effervescent bubbling of hydrogen peroxide was misinterpreted as a sign of vigorous germ-killing, leading to its widespread use as a disinfectant. However, later research revealed that this process also kills the body's healthy cells, slowing down the healing process.

For most minor wounds, the best practice is to gently wash the area with clean, running water and mild soap. This removes debris without damaging the delicate skin cells needed for healing. Afterwards, apply a thin layer of petroleum jelly and cover with a sterile bandage.

No, you should not use hydrogen peroxide to treat acne. It is too harsh for facial skin and can cause irritation, inflammation, and dryness. It also lacks targeted benefits for acne compared to proven topical treatments like benzoyl peroxide or salicylic acid.

Standard 3% hydrogen peroxide is not recommended for use as a mouthwash due to its harshness and the risk of accidental ingestion. Though diluted versions are sometimes used in a professional dental setting, it's safer to stick to mouthwashes specifically formulated for oral hygiene.

Avoid using hydrogen peroxide on sensitive surfaces such as untreated wood, natural stone countertops (marble, granite), and certain metals like copper, brass, and aluminum. It can cause discoloration, corrosion, and damage protective finishes.

While not a typical allergy, some individuals can experience skin irritation, redness, burning, and even blistering from contact with hydrogen peroxide, especially on sensitive skin. If you experience a reaction, wash the area thoroughly and stop use.

Store hydrogen peroxide in its original dark, opaque bottle in a cool, dark place, as light and heat cause it to decompose into water. Once opened, its effectiveness diminishes over time, so it's a good idea to replace it every six months to a year.