Tranexamic Acid for Heavy Periods: Uses and Side Effects

Tranexamic acid is a tablet that makes heavy periods lighter. It helps your blood to clot, it contains no hormones, and you take it only on the days you bleed. In the trials, the blood lost in a period fell by nearly 40%.

This guide explains how it works, how to take it, the side effects, who should not take it, and what to write down. It is general information and not medical advice. Your own doctor or pharmacist can tell you if it is right for you.

If you are not sure your periods count as heavy, start with our guide to the signs you are losing too much blood. This page is only about tranexamic acid.

What tranexamic acid is and how it works

Tranexamic acid is in a group of medicines called antifibrinolytics. Your body makes clots to stop bleeding, and it also makes enzymes that break clots down. People with heavy periods have more of a clot-dissolving enzyme in the womb lining and in period blood. Tranexamic acid lowers that activity, so it stops clots from breaking down as fast and the bleeding is less.

Some facts help to set your expectations:

• It is not a hormone. The tablets do not contain any hormones. They do not affect your fertility, and you cannot use them as birth control.
• It does not stop your period. It lowers the amount of blood you lose, and your period still comes.
• It is not a painkiller. It works on bleeding only. Anti-inflammatory painkillers (NSAIDs) are the other non-hormonal option for heavy periods. Our guide to what helps period cramps covers pain relief.

In the US, a brand name is Lysteda. In the UK, brand names are Cyklokapron and Evana Heavy Period Relief.

How much does tranexamic acid reduce bleeding?

Two US trials tested it in people who lost 80 mL of blood or more in a period. Here are the results for the usual dose:

People who took it also had fewer limits on social, leisure and physical activities during their period. About 40% of the people in these trials had fibroids.

It can take up to 24 hours to work fully. Give it a fair test. If your periods are no lighter after 2 cycles, or it seems to stop working, talk to your doctor.

How and when to take it

Start the tablets when your period starts. Do not take them before your period, or on days when you do not bleed.

The usual US dose is 1,300 mg (two 650 mg tablets) three times a day, for no more than 5 days in each period. People with kidney problems need a lower dose. In the UK, you usually take it 3 times a day for a few days at a time. Always follow the dose on your own prescription or pack.

• Swallow the tablets whole. Do not split, chew or crush them. You can take them with or without food.
• Stay under the daily limit. Do not take more than 6 tablets in 24 hours.
• If you miss a dose, take it when you remember. Then wait at least 6 hours before the next one. Never take more than two tablets at a time to catch up.

How you get it depends on where you live. In the US, tranexamic acid tablets are a prescription medicine. In the UK, adults aged 18 and over can also buy it from a pharmacy for heavy periods.

Tranexamic acid side effects

Most people do not have any side effects from the tablets. In the US trials, the most common complaints were:

• headache
• sinus and nose symptoms, such as a blocked nose
• back pain and belly pain
• muscle and joint pain, and muscle cramps
• migraine
• anaemia and tiredness

Most of these were almost as common in people who took a dummy pill. For example, about half of each group had a headache. Tell your doctor about any side effect that is bad or does not go away.

Serious side effects are rare. Stop the tablets and get medical help at once if you have signs of a blood clot, changes in your vision, or an allergic reaction. The urgent help section below lists the signs.

Who should not take tranexamic acid

Do not take tranexamic acid if you:

• have a blood clot now, have ever had one, or have been told you are at risk of one, for example because of a clotting disorder
• use combined hormonal birth control (see the next section)
• are allergic to tranexamic acid

Talk to a doctor before you take it if you:

• have epilepsy or kidney problems
• are pregnant or trying to get pregnant
• have irregular periods, so a doctor can check the cause of the bleeding first
• have periods that start less than 21 or more than 35 days apart
• are breastfeeding, or take other medicines, such as medicines that help your blood clot or break up clots

It is not meant for use after menopause.

Tranexamic acid and the combined pill

Combined hormonal birth control has both oestrogen and a progestin. It includes the combined pill, the patch and the vaginal ring. This is one point where US and UK advice differ.

The US label says do not take tranexamic acid with combined hormonal birth control. Together, they may raise the risk of a serious blood clot, stroke or heart attack. The risk is of most concern in people who smoke, especially smokers over 35, and in people with obesity. The NHS advice is to speak to your doctor if you take the combined pill, because there is a very small increased risk of a DVT (a clot in a deep vein).

In either country, tell your doctor or pharmacist about all the birth control you use before you start tranexamic acid.

Heavy periods with adenomyosis, fibroids or endometriosis

Heavy bleeding often has a cause, and the cause can change which treatment a doctor offers first.

• Adenomyosis, small fibroids or no cause found. A hormonal coil (LNG-IUS) is usually the first treatment to consider. If you do not want one, or it does not suit you, tranexamic acid and NSAIDs are the non-hormonal options. Read about adenomyosis symptoms and the adenomyosis belly.
• Fibroids of 3 cm or more. Doctors can offer tranexamic acid and/or NSAIDs while tests and longer-term treatment are arranged. You can keep taking them for as long as they help.
• Endometriosis. If heavy periods come with a lot of pain, the pain may come from endometriosis rather than adenomyosis. See the common symptoms of endometriosis.

Tranexamic acid can make the bleeding lighter. The pain and the condition behind it still need their own plan. Our guide to endometriosis treatment options compares the main choices.

What to track while you take it

A simple record shows you and your doctor if the tablets help. Start one period before you take them if you can, so you have a baseline. For each day of bleeding, write down:

• Flow. How many pads, tampons or cup changes you needed, and how fast each one filled.
• Clots. How many, and their size compared with a coin. Our guide to blood clots during your period explains which clots are common.
• Nights. If you woke up to change, or leaked onto your sheets.
• Doses. The days and times you took a tablet, and any missed doses.
• Side effects. Headaches, aches, tiredness or anything new.
• Pain. A score from 0 to 10, since tranexamic acid does not treat pain.
• Missed plans. Work, school or exercise you skipped because of bleeding.

After two periods on the tablets, compare them with your baseline. Our guide to a pain diary for your doctor shows how to bring a record like this to an appointment. Endolog is a pain and symptom diary app, and you can log flow, clots, pain and medicines each day in one place.

When to see a doctor

Book an appointment if:

• your periods are no lighter after 2 cycles on tranexamic acid, or it seems to stop working
• your bleeding pattern changes in a way that worries you, or your heavy bleeding goes on, as this can be a sign of a more serious condition
• your bleeding gets worse during treatment
• your periods are irregular, so a doctor can check the cause

Our guide to the signs you are losing too much blood covers low iron and the other warning signs in more detail.

When to get urgent help

Some signs need care the same day. Call 911 in the US or 999 in the UK when the table says so.

If you feel faint or you could be pregnant, read the urgent help section in our guide to heavy period bleeding.

Frequently asked questions

Does tranexamic acid stop your period?

No. It lowers the amount of blood you lose but does not stop your period. In the trials, blood loss fell by nearly 40%.

Is tranexamic acid a hormone?

No. The tablets contain no hormones. They do not affect fertility and do not work as birth control.

How fast does tranexamic acid work?

It can take up to 24 hours to work fully. You take it only during your period, starting when the bleeding starts.

Can I take tranexamic acid with ibuprofen?

Doctors can offer tranexamic acid and NSAIDs together for heavy periods. Ibuprofen is an NSAID. Ask your doctor or pharmacist first, and tell them about any other medicines you take.

Can I buy tranexamic acid over the counter?

In the UK, adults aged 18 and over can buy it from a pharmacy for heavy periods. In the US, the tablets are a prescription medicine.

This article is for general information. It is not medical advice and does not replace advice from your own doctor or pharmacist. If you think you have an emergency, call 911 in the US or 999 in the UK.