Red Light Therapy Contraindications: 9 Risks you MUST know before trying RLT (Copy)

Published: April 29, 2026

Last Updated: April 29, 2026

Estimated Reading Time: 8 minutes

Red light therapy (RLT) isn’t for everyone—some conditions make it unsafe. Always chat with your GP or specialist if you’re unsure whether RLT is right for you. Photosensitivity, pregnancy, and active cancer are major red flags. Safe alternatives exist if RLT isn’t suitable for you. Start slow and monitor your body’s response.

Introduction: Is Red Light Therapy Safe for You?

Red light therapy (RLT) is a game-changer for many—promoting healing, reducing inflammation, and boosting skin health. But here’s the thing: it’s not a one-size-fits-all solution. Just like any treatment, it has contraindications—specific conditions or situations where RLT could do more harm than good.

Ignoring these could lead to skin irritation, burns, or even worsen underlying health issues. The good news? Most of these risks are avoidable if you know what to look out for.

In this guide, we’ll break down:

- 9 critical contraindications for red light therapy.

- Why your GP’s advice is non-negotiable if you’re unsure.

- Safe alternatives if RLT isn’t right for you.

- How to use RLT responsibly if it is suitable for you.

Let’s dive in.

What Are Contraindications?

Contraindications are medical or health-related reasons that make a treatment unsafe or unsuitable for someone. In plain English? They’re the "red flags" that tell you: "Maybe skip this one."

For red light therapy, contraindications include:

- Medical conditions (e.g., active cancer, lupus).

- Medications that make your skin or eyes extra sensitive.

- Pregnancy or breastfeeding.

- Recent injuries or infections.

Why does this matter? Because your safety comes first—and RLT should only be used when it’s the right choice for your body.

If you’re ever unsure, your GP or a trusted specialist is your best resource. They know your health history and can help you decide if RLT is a good fit.

Who Should Avoid Red Light Therapy? 9 Critical Contraindications

1. Active Cancer or Suspicious Lesions

Why it’s risky:

RLT stimulates cell activity, which could accelerate the growth of cancer cells in active tumors. While some studies explore RLT as a complementary therapy for cancer patients, it should never be used on cancerous areas without direct supervision from an oncologist.

What the experts say:

"The major contraindications for the use of light therapy are diseases that involve the retina of the eye, such as diabetes, and the use of certain medications that increase sensitivity to light."

[News-Medical.Net](https://www.news-medical.net/health/Light-Therapy-Safety-and-Side-Effects.aspx)

What to do:

If you have a history of skin cancer or active cancer, talk to your oncologist before even considering RLT. Never use RLT on cancerous areas unless explicitly advised by your doctor.

2. Photosensitive Conditions (Lupus, Porphyria, Solar Urticaria)

Why it’s risky:

RLT exposes your skin to specific wavelengths of light, which can trigger flare-ups in people with heightened light sensitivity. Conditions like lupus, porphyria, and solar urticaria can worsen with light exposure.

What the experts say:

"Photosensitivity—heightened sensitivity to light—is one of the primary contraindications for red light therapy. If you have lupus or porphyria, RLT could make your symptoms worse."

[Rouge Care](https://www.rouge.care/blogs/news/possible-contraindications-of-red-light-therapy)

What to do:

If you have a photosensitive condition, avoid RLT unless your doctor says otherwise. Test a small area first if you’re curious—but watch for redness, itching, or rashes.

Quick Check:

Do you have lupus or porphyria?

Does sunlight trigger your symptoms?

If yes, skip the RLT and ask your doctor for safer alternatives.

3. Pregnancy or Breastfeeding

Why it’s risky:

There’s not enough research on how RLT affects pregnant or breastfeeding women. To play it safe, most healthcare providers recommend avoiding RLT during this time.

What the experts say:

"Pregnancy or nursing is a contraindication for red light therapy. While generally safe for others, there isn’t enough evidence to confirm its safety during pregnancy or breastfeeding."

[MedcoVet](https://medcowellness.com/contraindications-for-red-light-therapy/)

What to do:

Hold off on RLT if you’re pregnant, trying to conceive, or breastfeeding. Ask your obstetrician or GP for personalised advice.

4. Photosensitive Epilepsy

Why it’s risky:

The flashing or bright light from RLT devices may trigger seizures in people with photosensitive epilepsy.

What the experts say:

"Photosensitive epilepsy is a contraindication for red light therapy. The light could induce seizures in susceptible individuals."

[Foreo](https://www.foreo.com/red-light-therapy/who-should-not-use-red-light-therapy/)

What to do:

If you have epilepsy, avoid RLT unless your neurologist says it’s safe. Always use RLT in a well-lit room to reduce flicker effects.

Important:

If you or a loved one has epilepsy, consult a neurologist before trying RLT.

5. Eye Diseases or Retinal Conditions (Diabetic Retinopathy, Macular Degeneration)

Why it’s risky:

RLT can affect the eyes, so people with retinal conditions should avoid direct exposure. Conditions include:

- Diabetic retinopathy

- Macular degeneration

- Retinitis pigmentosa

- Untreated cataracts

What the experts say:

"Safety measures for light therapy include avoiding use in individuals with diseases that involve the retina of the eye, such as diabetes."

[News-Medical.Net](https://www.news-medical.net/health/Light-Therapy-Safety-and-Side-Effects.aspx)

What to do:

Never shine RLT directly into your eyes. If you have an eye condition, see an ophthalmologist before trying RLT. Wear protective goggles if you’re using RLT on your face.

Pro Tip:

Protect your eyes! Always use RLT goggles if treating your face or using a full-body panel.

6. Recent Burns or Open Wounds

Why it’s risky:

RLT may interfere with healing or spread bacteria in open wounds or recent burns.

What the experts say:

"Active infections and open wounds may contraindicate red light therapy. It could spread pathogens or slow down natural healing."

[Safe Usage Guide](https://www.safeusagedguide.com/contraindications-for-red-light-therapy/)

What to do:

Wait until the area is fully healed before using RLT. If you have acne or eczema flare-ups, give your skin time to recover.

7. Taking Photosensitizing Medications

Why it’s risky:

Some medications increase sensitivity to light, making RLT unsafe. These include:

- Tetracyclines (e.g., doxycycline for acne).

- Retinoids (e.g., isotretinoin for acne).

- Psoralens (used for psoriasis).

- Certain chemotherapy drugs.

- St. John’s Wort (herbal supplement).

What the experts say:

"People who take medications that increase their skin or eye sensitivity should not use red light therapy."

[WebMD](https://www.webmd.com/skin-problems-and-treatments/red-light-therapy)

What to do:

Check with your GP or pharmacist if your medication interacts with light therapy. Keep a list of your meds handy when researching RLT devices.

Quick Check:

Are you on antibiotics, acne meds, or antidepressants?

Do you take herbal supplements like St. John’s Wort?

If yes, ask your doctor before trying RLT.

8. Active Infections (Bacterial, Fungal, or Viral)

Why it’s risky:

RLT may worsen inflammation or spread infections in active cases.

What the experts say:

"Active infections are a contraindication for red light therapy. It could exacerbate the condition or spread pathogens."

[Safe Usage Guide](https://www.safeusagedguide.com/contraindications-for-red-light-therapy/)

What to do:

Let infections fully clear before using RLT. If you have cold sores, acne, or athlete’s foot, wait until they’re gone.

9. Undiagnosed Pain

Why it’s risky:

RLT may mask symptoms of a serious underlying issue, delaying proper diagnosis.

What the experts say:

"Undiagnosed pain is a contraindication for red light therapy. It could interfere with proper diagnosis and treatment."

[MedcoVet](https://medcowellness.com/contraindications-for-red-light-therapy/)

What to do:

Never use RLT for unexplained pain without seeing a doctor first. Get a proper diagnosis before trying RLT as a pain relief method.

Important:

Persistent pain? See your GP—don’t rely on RLT to "fix" it without knowing the cause.