Tranexamic acid

What is tranexamic acid?

Tranexamic acid is a medicine that’s commonly used to control bleeding. Developed in 1962 by Japanese researchers, its wide range of uses (such as helping to prevent blood loss for trauma patients in hospitals to treating heavy periods or nosebleeds for people at home) have led the WHO to place it on their list of essential medicines.^[1] It’s available on prescription in the form of tablets, liquid, mouthwash and (in hospital settings) injections.

More recently, it’s been shown to be a safe and effective treatment for certain conditions related to skin pigmentation, such as melasma. It may be prescribed by dermatologists to even out your skin tone (in low doses). According to recent studies, it can work for up to nine in ten people, without many risks.^[2] But it’s still an ‘off-label’ treatment when used for skin conditions. This means that tranexamic acid isn’t licensed to treat skin conditions, but dermatologists can still prescribe it for this purpose if they think it’ll be safe for you.

How does tranexamic acid work?

For its licensed uses, tranexamic acid works by supporting your body’s natural clotting process, which speeds up the rate at which you stop bleeding. But for dermatological conditions, it’s not fully known how it works to improve symptoms. A commonly held theory is that it works by both causing your skin’s blood vessels to become smaller, and reducing your melanin production (the pigment that gives skin its colour). It does this by changing the way certain skin cells (keratinocytes and melanocytes) interact with each other, and by decreasing the activity of an enzyme called tyrosinase.

What doses of tranexamic acid are there?

Tranexamic acid comes as 500mg tablets. Typically, for something like heavy periods, you’ll be advised to take two or three tablets, three times a day while you’re on your period. However, for melasma, the recommended daily dosage is much lower – 500mg per day. You may be advised to split this across two doses (of 250mg each), one in the morning and one at night. Your dermatologist will give you precise instructions on how best to take tranexamic acid to suit your needs.

How to use Tranexamic acid for melasma

Make sure to follow your dermatologist’s instructions carefully when taking tranexamic acid for melasma.

To take the tablets, simply swallow them whole, with water. You can take it with or without food. Try to spread your doses evenly across the day.

If you’re taking the liquid, it will come with a plastic syringe or spoon to help you measure out your dose. Don’t use a kitchen spoon as the dose won’t be accurate. (If your treatment didn’t come with a syringe or spoon, ask your pharmacist for one.)

For melasma, tranexamic acid can be taken orally or used topically (applied directly to your skin). Oral tranexamic acid is off-label, and should only be prescribed by a licensed clinician. They’ll decide how much you should use (and how long for) based on your medical profile.

How long before it starts to work?

The length of time it takes tranexamic acid to work will depend on what you’re using it to treat. For reducing bleeding, it can take up to 24 hours for it to work fully, but for skin conditions it’ll take a bit longer.

Tranexamic acid is generally safe to use for extended periods of time. For conditions where longer treatment periods are needed, it’ll take eight to 12 weeks of consistent treatment before you start to see the full effects of it. If your skin hasn’t improved after this time, speak to your dermatologist.

What should I do if I take too much or miss a dose?

If you forget your dose of tranexamic acid, take it as soon as you remember (unless it’s nearly time for your next dose). If it is, simply skip that dose and carry on as normal. Don’t take a double dose to make up for the forgotten one. If you often find yourself missing doses, you might find it useful to set an alarm to remind you.

If you do accidentally take an extra dose of tranexamic acid, it’s unlikely to cause any problems. However if you take too much it can cause side effects, such as nausea, sickness, diarrhoea and dizziness. Seek medical help if you’re worried or these side effects are concerning you.