Management of pain in endometriosis

Some women prefer to avoid hormone therapy or surgery and can manage their symptoms using painkillers and other treatments.
General measures to relieve endometriosis-associated pain include a broad approach of understanding the disease and avoiding pain triggers (such as certain positions during sexual intercourse), participating in as many ‘well-behaviours’ as possible such as exercise and socializing, and trying to reduce ‘maladaptive behaviours’ such as excessive reliance on medication, bed rest and a restricted lifestyle.

Treatment with painkillers alone may be sufficient for some women with endometriosis-related pain. However, for many women with endometriosis painkillers alone do not provide adequate relief from the pain, although they may be used in addition to other treatments.

Although painkillers may be effective in some women there is little evidence to indicate which types work best in endometriosis.


Anti-inflammatory painkillers (NSAIDs) – Nonsteroidal anti-inflammatory drugs (NSAIDs) are a group of painkillers that also have an anti-inflammatory effect. Commonly used NSAIDs for period related pain include ibuprofen, mefenamic acid, naproxen and diclofenac. As endometriosis is a condition which results in inflammation NSAIDs are recommended as the first choice of painkiller, unless the patient has a reason why these drugs are not suitable. While there is good evidence that NSAIDs are effective in the treatment of simple period pain not caused by endometriosis, there is less evidence regarding their effectiveness in managing pain specifically caused by endometriosis.
Some people may experience side-effects with NSAIDs which include nausea, vomiting, diarrhoea, stomach upsets and ulcers. These side effects can be reduced by taking the drugs with food or milk and by using a low dose for short periods of time. Although no particular NSAID has been shown to be more effective than another, ibuprofen is usually the preferred choice as it has lowest risk of side effects. Aspirin is less effective than other NSAIDs in the treatment of period pain and is therefore not recommended.

Other painkillers – Paracetamol taken during periods (with or without added codeine) may provide adequate pain relief for women with mild symptoms.
It may be a suitable alternative in women who are unable to use NSAIDs.

Paracetamol has been shown to be effective in relieving simple period pain so therefore is likely to relieve pain in some women with endometriosis. Most individuals can take paracetamol without experiencing significant side effects.

Codeine-based painkillers are effective, but can cause constipation and gastrointestinal side effects.

Other pain management options

There are other options for pain management. Physical methods including heat from a hot bath or water bottle, physiotherapy and TENS (transcutaneous electrical nerve stimulator) machines may help to ease pain. Pain modifying drugs are sometimes prescribed and these work by altering the body’s perception of pain.

Pain clinics

Some hospitals have dedicated pain clinics where experts can provide specialist treatment, advice and support to people with chronic pain which has not responded well to the usual treatments.

Hormonal treatment of endometriosis-associated pain
Hormonal treatments that prevent ovulation (release of the egg from the ovary) are effective at relieving pain associated with endometriosis, but will not improve fertility.

Hormone treatments work by causing endometriosis deposits to shrink. Oestrogen is a hormone produced by the ovaries that stimulates endometrial tissue (the cells lining the inside of the womb) to grow and bleed. In endometriosis the endometrial tissue which is outside the uterus can also grow and bleed in response to oestrogen. Hormone treatments for endometriosis work by either reducing the blood levels of oestrogen, or by changing the effect that oestrogen has on the endometrial tissue. Patches of endometriosis gradually shrink and may eventually disappear.
It is unlikely that hormone treatment affects the cause of endometriosis. Consequently such treatment may not always provide complete pain relief and some women may not improve at all. Hormonal treatment would not be expected to improve symptoms caused by adhesions or scar tissue.

There are several hormone treatment options. All have similar success rates at easing moderate to severe pain when used for six months, although they have different side effects. The high costs and side effects of some of these treatments may limit their long term use and women may choose to stop treatment. Some women may respond to one treatment better than another, and it may be necessary to try several different treatments if the first does not improve symptoms or causes intolerable side effects.

Hormonal treatments include combined oral contraceptive pills, progestogens, androgens (danazol, gestrinone), and gonadotrophin-releasing hormone (GnRH) analogues. The treatments which stop periods altogether (GnRH analogues and danazol) are especially successful at treating period pain.

Recurrence of symptoms after stopping hormone treatment is common and repeated courses or different treatments may be necessary.

The combined oral contraceptive pill (the Pill)

The pill is commonly used to treat symptoms of endometriosis. Periods become regular, lighter and less painful. It contains a mixture of hormones similar to oestrogen and progesterone, which prevents ovulation (release of the egg from the ovary).

Some women can be advised to ‘tricycle’ packets of pills (take 3 packets of pills back to back followed by a week without pills) to reduce the frequency of periods and therefore pain symptoms.

The pill may be the preferred treatment if contraception is also needed. There are many pill formulations available which may produce different side effects in some women. Side effects can include breakthrough bleeding, breast tenderness, weight gain, acne, and mood changes. Women may need to try different brands until they find one that suits them.

Progestogen hormone tablets
Progestogens are hormones which reduce the effect of oestrogen on the endometrial cells, causing the endometriosis to shrink. Progestogens also prevent ovulation which lowers the oestrogen levels. There is evidence that progestogens can improve symptoms caused by endometriosis. Different progestogen treatments include norethisterone, dydrogesterone and medroxyprogesterone tablets. These can be taken on a daily basis, or in cycles with some time off. While taking progestogen tablets periods should stop, but bleeding will usually occur within days of stopping the tablets (a withdrawal bleed).

Side-effects that may occur include irregular menstrual bleeding, weight gain, mood changes, and fluid retention. Additional contraception is recommended (barrier methods such as condoms) as progestogens used for endometriosis do not provide reliable contraception.


Danazol and gestrinone are sythentic (manufactured) androgen hormones. Androgens are predominantly male hormones but can be used in women to reduce the production of the female hormones oestrogen and progesterone. Consequently there is less stimulation of the endometriosis deposits and they can often shrink in size with an improvement in symptoms. Many women stop having periods while taking androgen treatment.

Side-effects are common and include weight gain, hair growth, acne, and mood changes. Rarely, it causes a deepening of the voice which may be irreversible. Androgens are effective at treating symptoms caused by endometriosis, however many women cannot tolerate the side effects. Androgens are therefore not commonly prescribed for endometriosis unless other treatments have been tried without success. Androgens are usually only prescribed for six months. Additional non-hormonal contraception (barrier methods such as condoms) must be used if needed as androgens are not reliable contraceptives and androgens can have serious adverse effects on the developing fetus.

Gonadotrophin Releasing Hormone Analogues (GnRH analogues)
GnRH analogues are modified versions of the naturally occurring hormone gonadotropin releasing hormone (GnRH). This hormone is released from the brain and helps to control the menstrual cycle. If given continuously for more than two weeks, GnRH analogues will cause a temporary menopause by stopping the release of oestrogen from the ovaries. Ovulation and periods will stop in most women receiving GnRH analogues. Very low levels of oestrogen will cause endometriosis to shrink and become inactive.

GnRH analogue drugs include buserelin, goserelin, nafarelin, leuprorelin, and triptorelin. Some preparations are taken as an injection, whilst others may be given as a nasal spray. If contraception is required during treatment, non hormonal method (such as condoms) should be used.

Side-effects are commonly caused by the very low levels of oestrogen that occur during this treatment, and are very similar to symptoms experienced by women who are going through the menopause. These include hot flushes, vaginal dryness, reduced sex drive, headaches, and difficulties with sleeping (another effect of treatment with GnRH analogues is that they can cause the bones to become less dense).

A course of GnRH analogue treatment is usually given for only for six months. This is because prolonged courses will reduce the density of the bones even further. However, some specialists may recommend that repeated or longer courses may be appropriate for some women. For example, treatment can be taken intermittently with or without ‘add back therapy’ (see below). Alternatively, continuous treatment for up to two years with add-back therapy may be recommended for some women. This appears to be effective for pain relief and safe for bone density.

‘Add-back therapy’ is where women being treated with GnRH analogues are given low dose hormone replacement therapy in order to reduce the menopausal-like side effects caused by very low oestrogen levels, and to lessen the effects that GnRH treatments have on reducing the bone density.

Add-back therapy has been shown to reduce the loss of bone density and to improve symptoms. The ultimate goal of add-back therapy is to improve compliance (so that fewer women stop taking GnRH analogues because they cannot tolerate the side effects) and to maximize the length of time GnRH analogues can be used for. There are different choices of hormone treatments used for add-back therapy, although there is a lack of evidence to guide best treatment regime. Options include low dose oestrogen, low dose oestrogen given with a progestagen or tibolone. Tibolone is a synthetic hormone which mimics the action of both oestrogens and prgestagens in the body and is a popular choice for add-back therapy.

Levonorgestrel Intrauterine System (LNG-IUS)

The LNG-IUS is a small plastic T-shaped device that is inserted into the uterus (like a contraceptive coil). It contains a progestagen called levonorgestrel. The hormone is released slowly into the uterus. The hormone acts to make the endometrium in the uterus thin, which usually results in light periods and in some women periods stop all together. The LNG-IUS is usually used as a contraceptive; however it is sometimes used to treat the symptoms of endometriosis. Although only a few studies have been carried out, the evidence suggests that the LNG-IUS can be effective in reducing endometriosis associated pain.

Hormonal treatment for infertility

There is no evidence to support the use of hormonal treatments in endometriosis to improve fertility. Most of the hormonal treatments also act as contraceptive. Therefore hormonal treatment should not be used for women trying to conceive naturally as they are not effective and will reduce the opportunity to conceive.

Publication Date: 02 Apr 2007
Publication Type: Patient Information
Publisher: Women’s Health Specialist Library
Creator: Women’s Health Specialist Library