A New Daily Pill for Endometriosis Reaches the NHS

A new option for endometriosis has arrived on the NHS

For the first time in years, people with endometriosis in the UK have a genuinely new medicine to consider. The National Institute for Health and Care Excellence (NICE) has recommended linzagolix, sold under the brand name Yselty and made by Theramex, for use on the NHS in England, with the same access following in Wales and Northern Ireland.

The recommendation, published in 2025, opens the door to a once-daily tablet taken at home for people whose endometriosis has not been controlled by earlier treatments. NHS England estimates that more than 1,000 women a year could benefit. After years of campaigning about how few options exist, this is a meaningful addition, even though it is not a cure.

This article explains what linzagolix is, how it works, who is eligible, what the trial evidence actually shows, and how it sits alongside the treatments already in use.

What endometriosis is, briefly

Endometriosis is a chronic condition where tissue similar to the lining of the womb grows in other parts of the body, most often around the pelvis. This tissue responds to hormonal changes across the menstrual cycle, building up and breaking down, which can drive inflammation, scarring and pain.

Common symptoms include painful periods, pelvic pain between periods (non-menstrual pelvic pain), pain during or after sex, pain when going to the toilet, fatigue and, for some people, difficulty conceiving. It is a common condition, affecting roughly one in ten women and people who menstruate of reproductive age, yet diagnosis is often slow because symptoms are dismissed or mistaken for ordinary period pain.

If you are unsure whether your symptoms point to endometriosis or to typical menstrual discomfort, our period pain versus endometriosis pain guide walks through the differences.

The treatment gap this fills

For a long time, the standard options have been the contraceptive pill or other hormonal contraceptives, progestogens, GnRH agonist injections, pain relief, and surgery to remove endometriosis tissue. Many people cycle through several of these, and some find that none of them controls their symptoms well.

Endometriosis UK has been clear that there are far too few treatment options, a situation it links to a historic lack of research funding into the condition. When earlier treatments stop working or are not tolerated, the choices narrow quickly. Linzagolix matters because it is aimed squarely at that group: people who have already tried other medical or surgical treatments and still need help.

What linzagolix is and how it works

Linzagolix is an oral gonadotropin-releasing hormone (GnRH) antagonist. That is a precise way of saying it works on the hormonal signals that control the menstrual cycle.

In a typical cycle, the brain releases GnRH, which prompts the pituitary gland to signal the ovaries to produce estrogen. Estrogen is the hormone that drives the growth of endometrial-like tissue, both inside and outside the womb. Linzagolix attaches to GnRH receptors in the pituitary gland and blocks that cascade, lowering estrogen and putting the body into a state often described as a medical menopause. With less estrogen circulating, the abnormal tissue is starved of the signal that makes it grow, and endometriosis-associated pain tends to ease.

Why it is taken with add-back HRT

Lowering estrogen is the point, but estrogen also protects against side effects. Dropping it too far for too long can cause menopause-like symptoms such as hot flushes, and can reduce bone mineral density over time. To counter this, linzagolix for endometriosis is prescribed at the higher dose alongside hormonal add-back therapy, which is a small, steady amount of estrogen and progestogen.

This add-back HRT is the clever part of the design. It tops up just enough hormone to limit bone loss and ease menopausal effects, while still keeping estrogen low enough to control the disease. The treatment is taken as a single tablet once a day, which is far simpler than older approaches that required regular injections.

Who is eligible

NICE recommends linzagolix with add-back therapy for adults of reproductive age who have endometriosis and have already tried other medical or surgical treatments without adequate relief. It is not a first-line treatment, and it is not something you would expect to be offered before standard hormonal options or pain management have been explored.

In practice this means linzagolix is a specialist-prescribed medicine, typically arranged through gynaecology or endometriosis services rather than handed out at a first GP visit. Eligibility depends on your treatment history, your bone health, and whether add-back HRT is suitable for you. The NHS in England is required to make a NICE-recommended treatment available within 90 days of final guidance, so availability has been rolling out through services.

What the trial evidence shows

The recommendation rests largely on the EDELWEISS 3 trial, a randomised, double-blind, placebo-controlled Phase 3 study. It tested linzagolix in women with moderate-to-severe endometriosis-associated pain, including a 200 mg once-daily dose combined with add-back therapy.

The results were measured against two co-primary endpoints: reduction in dysmenorrhoea (painful periods) and reduction in non-menstrual pelvic pain. Linzagolix with add-back therapy produced statistically significant reductions in both, compared with placebo, and did so while patients used the same amount of pain relief or less.

The size of the effect is worth noting. At 12 weeks, the proportion of people responding for overall pelvic pain was around 56 to 61 percent at the active doses, against roughly 35 percent for placebo. Benefits appeared by week 12 and were maintained through to week 52 at doses of 75 mg or higher, which suggests the relief holds up over a year rather than fading quickly. NICE judged the medicine to be cost-effective within its accepted range and to offer similar benefits at a comparable cost to existing choices.

How it compares to other options

It is easy to confuse the recent endometriosis approvals, so it helps to disambiguate.

Versus GnRH agonist injections. Older GnRH agonists also lower estrogen, but they are usually given by injection and cause an initial hormonal flare-up, a temporary surge before levels fall, which can briefly worsen symptoms. They can also be slow to reverse once stopped. Linzagolix, as a GnRH antagonist, works without that flare-up, is taken as a daily oral tablet, and is rapidly reversible, so hormone levels return to normal relatively quickly after stopping, which matters for anyone who may want to conceive later.

Versus the relugolix combination pill. Shortly before linzagolix, NICE recommended Ryeqo, a combination pill of relugolix, estradiol and norethisterone acetate, described as the first long-term daily pill for endometriosis. Ryeqo bundles the GnRH antagonist and the add-back hormones into one fixed product. Linzagolix is also a daily pill, but it keeps the add-back therapy separate, which allows a clinician to tailor the hormone component, or adjust it, for people for whom a fixed combination is not suitable. In short, the two are similar in spirit but differ in flexibility.

Versus surgery. Laparoscopic surgery can remove or destroy endometriosis tissue and is sometimes the right choice, especially for diagnosis or for specific lesions. But surgery carries operative risks, recovery time, and a chance that tissue regrows. Medicines like linzagolix are about ongoing symptom control rather than physically removing tissue. For many people the two are complementary rather than competing.

Across all of these, the same caveat holds: linzagolix manages symptoms; it does not cure endometriosis, and symptoms can return when treatment stops.

What to do next

If you think linzagolix might be relevant to you, the most useful thing you can do is arrive at your appointment with clear, organised information about your symptoms and treatment history. Here is a practical, doctor-ready approach.

1. Track your pain daily. Note where it is (period pain versus pelvic pain between periods), how severe it is, and how it changes across your cycle. Eligibility is built around people whose pain persists despite earlier treatment, so a clear record matters.
2. Log your bleeding and cycle. Record period start and end dates, flow and any breakthrough bleeding so your clinician can see the full pattern.
3. Write down what you have already tried. List previous medications, hormonal treatments, pain relief and any surgery, with rough dates and how well each worked. This treatment history is central to whether linzagolix is appropriate.
4. Note how symptoms affect daily life. Days off work or study, sleep, and activities you avoid all help convey severity.
5. Ask about bone health and add-back HRT. Because the medicine lowers estrogen, ask your clinician how your bone density will be monitored and whether add-back therapy is suitable for you.
6. Ask to be referred to a specialist if needed. Linzagolix is specialist-prescribed, so a referral to gynaecology or an endometriosis service may be the right step.

If you want a structured starting point before that conversation, try our endometriosis symptom checker to help organise what you are experiencing.

Side effects and cautions

The same mechanism that makes linzagolix effective is also the source of its main cautions. By lowering estrogen, it can cause menopause-like side effects such as hot flushes, and it can reduce bone mineral density, with the effect being larger at higher doses. This is precisely why the endometriosis regimen pairs the higher dose with add-back HRT, and why bone density monitoring is part of treatment.

It is not suitable for everyone. If add-back HRT is not appropriate for you, or if you have certain bone health concerns, your clinician may steer you toward another option. Linzagolix is also not a contraceptive on its own, and conversations about pregnancy plans matter because the goal is to lower estrogen, the very hormone needed to conceive. As with any prescription medicine, the decision should be made with a specialist who knows your full history.

How Femora helps

The hardest part of getting the right treatment is often walking into an appointment able to show, not just describe, what your body has been doing. That is where consistent tracking pays off.

With Femora, you can log pain, flow, mood and symptoms day by day and bring a clear timeline to your clinician, exactly the kind of record that supports an eligibility conversation about treatments like linzagolix. You can capture how your pelvic pain behaves between periods, not only during them, which is a distinction that matters for endometriosis.

If you and your doctor do start a daily medicine, staying consistent is what makes it work. Femora's cycle-synced medication reminders help you take a once-daily pill at the same time each day and keep add-back therapy on track, so the regimen fits into your routine rather than the other way around.

The bigger picture

Linzagolix will not transform care for everyone, and it is right to be measured: it helps a specific group, it manages symptoms rather than curing the disease, and it requires specialist oversight and bone monitoring. But its arrival, close behind another new daily pill, signals something that has been missing for a long time in endometriosis care, which is momentum. After decades of underinvestment, there are now more tools, more choice, and a clearer recognition that endometriosis pain deserves serious treatment.

For anyone who has felt stuck after exhausting the usual options, more choice is genuinely good news. The next step is making sure clinicians and patients have the information they need to use it well, and that starts with understanding your own symptoms. If you are interested in how current clinical guidance is evolving, our overview of the 2026 ACOG endometriosis guidelines offers useful context.

Track your cycle, understand your body, and walk into your next appointment prepared. Download Femora to start logging your symptoms today.

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