Managing tendonitis is tricky. Exercise therapy is the best treatment, but some people struggle with exercise and need extra help. Injections work in some cases but carry risks. A GTN patch — a glyceryl trinitrate patch placed over a painful tendon — is a low-risk alternative. So does a GTN patch for tendonitis work, and how should you use one to support your exercise programme?

A GTN patch is one of several non-injection adjuncts to tendon rehab — alongside collagen supplements and shockwave therapy.

What are GTN patches?

GTN — also called nitroglycerin or glyceryl trinitrate — is best known for treating heart disease. When applied to the skin, it’s absorbed and dilates blood vessels, boosting blood supply to the heart. We also know GTN helps tendons heal. So for tendonitis, we place the patch directly over the painful tendon, allowing the GTN to be absorbed through the skin.

How does GTN improve tendonitis?

We don’t know exactly. GTN appears to raise nitric oxide levels, and nitric oxide seems to stimulate collagen synthesis and blood flow — driving tendon healing.

Recent studies show that a GTN patch over a painful tendon can lower pain. One systematic review found strong evidence of pain improvement with GTN patches plus exercise. But a more recent review casts doubt, suggesting only a borderline benefit for upper- and lower-limb tendonitis. Overall, the evidence is mixed — but patches are safe and non-invasive.

Which tendons respond to a GTN patch?

A GTN patch only helps tendons that sit just under the skin:

The best evidence comes from tennis elbow, Achilles tendonitis, and rotator cuff tendonitis.

How to use a glyceryl trinitrate patch for tendonitis

Use only the brand Deponit. It’s a matrix patch that doesn’t leak when cut — unlike other brands and generics, which cause more side effects and a less sustained effect.

Start low to limit side effects:

  • Cut the patch into quarters; start with 1/4 of the patch, and discard the unused portion.
  • Place the quarter patch on the skin over the most tender part of the tendon.
  • Apply in the morning, remove at night — you need a patch-free break of at least 8 hours daily.
  • Keep it on in the bath or shower, and you can exercise with it on.
  • After day 4, if no headache, increase to 1/2 patch.
  • After day 8, if no headache, increase to a whole patch.
  • For a headache, take paracetamol or reduce the dose. For a skin rash, move the patch slightly each day.

GTN patches are prescription-only. We usually use them for 2–3 months to support an exercise programme, occasionally up to 6 months.

Side effects of a glyceryl trinitrate patch

The commonest is headache — about one in three people. Take paracetamol, or reduce the dose (full → 1/2 → 1/4), then build back up as tolerated.

Skin rash is also common. Move the patch slightly each day — over the sore spot on day 1, then 1–2 cm above it, then to the side, rotating around the clock — or reduce the dose.

Avoid GTN patches with erectile dysfunction drugs such as Viagra and Cialis. If you use these, remove the patch — its effect wears off 15–30 minutes after removal.

Frequently asked questions about GTN patches for tendonitis

How long do GTN patches take to work for tendonitis?

A GTN patch doesn’t work immediately. Expect an effect after about four weeks, sometimes up to six. If there’s no improvement by six weeks, the patch is unlikely to help.

Do I need a prescription for GTN patches?

Yes. GTN patches must be prescribed by a doctor who understands the drug and its interactions. Avoid obtaining them from non-medical practitioners.

Are GTN patches addictive?

No. There’s no addiction risk and no need to wean off them.

Are GTN patches a better option than tendon injections?

We think so for many people. Patches have minimal side effects and are unlikely to worsen tendon pain, whereas injections are invasive, unpredictable, and can occasionally worsen pain.

Can I use a GTN patch if I get migraines or chronic headaches?

Yes, but your risk of a headache is higher. Start with a quarter patch and build up slowly. Even so, you may not tolerate it.

Can I combine a GTN patch with other treatments?

Yes. GTN patches work best alongside an exercise programme, and combine well with shockwave therapy, collagen supplements, and injections.

Final word from Sport Doctor London about the GTN patch for tendonitis

A glyceryl trinitrate patch is a non-invasive, low-risk option for tendonitis. Some people respond very well; others don’t tolerate the side effects, which mirrors the mixed evidence. It’s a good option for stubborn tendons that haven’t responded to exercise alone, and it’s available only on prescription.

To discuss whether a GTN patch is suitable for your tendon problem, contact Dr Masci’s team here or call +44 (0) 203 488 0350.

Other tendon information: