Advising on pain relief is only one aspect of the pharmacist role in endometriosis, write Jarrod McMaugh and Sam Flood
Endometriosis is a condition that pharmacists will see regularly, as the mainstay of symptom control for this painful condition include analgesics, hormonal medications, and the use of non-medication modalities such as heat packs.
Pharmacists will have regular contact with people who are experiencing these symptoms until such time that they access surgical treatment. People who are experiencing the symptoms endometriosis for the first time will require referral to their GP for differential diagnosis and consideration of treatment; as will those who have changing or new symptoms.
What is it?
Endometriosis is characterised by the formation of endometrial tissue in areas of the reproductive system that are outside of the uterus; for instance, the fallopian tubes, ovaries, and infiltrating into the muscles of the uterus. In some cases, endometrial tissue forms on organs and tissues that are not part of the reproductive system; cases have been reported where endometrial tissues affect organs such as the bowel, liver, abdominal wall, lungs, spine, and eyes.
This endometrial tissue in other part of the body is as responsive to the hormonal cycle as endometrial tissue in the uterus, with the same physiological effects such as blood vessel and tissue proliferation, menstrual shedding (including bleeding), release of prostaglandins, and pain.
It is important to remember that the uterus accommodates endometrial thickening and menstruation as part of the expected function of this organ. Discomfort may be present during menstruation, but endometrial thickening within the uterus leading up to menstruation or pregnancy should not cause discomfort.
When endometrium forms on other organs, the thickening of this tissue in response to hormonal cycles will cause discomfort and pain due to lack of space and pressure on these organs. In addition, the misplaced endometrium may cause scarring and inflammation that contributes to the discomfort and pain.
Formation of endometrium outside of the uterus may affect the function of other organs; constipation and/or diarrhoea is common, as is infertility, backaches, leg pain, and pain or discomfort during sex.
Why does it happen?
There is no explanation for endometriosis that has been conclusively proven to be the cause, although family history is a reliable predictor. One accepted explanation is retrograde menstruation, where blood and tissue from a menstrual period comes into contact with tissue outside of the uterus, and through some undefined mechanism is able to form new tissue.
Another explanation is metaplasia, where one tissue type changes to another (in this case, endometrial tissue). It is possible that either mechanism is present in different individuals.
Other theories include stem cells forming the wrong cell lines, or exposure to toxins in the environment; these theories have less evidence to support them.
Signs and symptoms
The most common symptom is pain and discomfort, which can present at any time throughout the menstrual cycle, depending on the impact of endometrium on organs outside of the uterus.
Endometrial tissue can cause adhesions between organs, and may even develop their own nerve supply, leading to a combination of referred pain (from affected organs) and direct pain from the lesion itself.
Disruption of affected organs will cause various symptoms as previously mentioned, including constipation or diarrhoea, urinary retention or incontinence due to pressure on the bladder, and infertility due to obstructions in the fallopian tubes or adhesions of the ovaries.
Treatment for endometriosis may involve laparoscopic surgical excision of lesions. Some people may not find this an acceptable option, but surgery tends to be definitive, in that pain, infertility, and impact on other organs can be decisively removed.
Pregnancy also has an impact on the progression of the disease. This may not be an acceptable option for various reasons. Due to the impact of endometriosis on fertility, suggesting pregnancy as a treatment option may cause more frustration and distress than solutions.
Hormonal medications play a role, with combined oral contraceptives showing some benefit in preventing the progression of lesions, and also provide relief from symptoms caused by existing lesions by affecting the hormonal influence on the menstrual cycle.
Oestrogen antagonists such as aromatase inhibitors are being trailed, with limited success. Progesterone may also be of some importance, as changes in the endometrial tissue caused by the hormonal cycle can be suppressed with the use of these agents.
Analgesics will be an important part of symptomatic relief; given the relapsing/remitting nature of pain and symptoms, exposure to opioids is likely. Discussion about the role of opioid-containing analgesics, their impact on side effects (especially where constipation is already a factor), and tolerance/dependence should occur regularly.
The role of the pharmacist
People with endometriosis may see pharmacists for this condition more often than other health professionals if their discomfort is mild or manageable. For those who are experiencing changing or troubling symptoms, referral is important to arrest development or progression of lesions and symptoms.
As pain is the most common symptom, pharmacists will have regular discussions around the best options for pain relief in endometriosis. Inflammation is a major factor in the pain caused by endometrial adhesions and scarring, while cramping may be associated with the uterine lining. NSAIDs thus play an important role in treating this pain. The use of paracetamol in combination with NSAIDs may provide improved pain relief, with referral to a doctor required if pain is not controlled adequately with this combination.
Pharmacists need to have regular discussions with people presenting with endometriosis to ensure that any progression in symptoms are investigated. Changes in the pain experienced; new or altered symptoms from the involvement of other organs; or changes in the regularity/irregularity of symptoms or the menstrual cycle should be cause for further discussion.
Review by a general practitioner or specialist may be warranted to investigate if these changes are a progression in condition, or signs of another issue altogether.
People experiencing symptoms of endometriosis may have a long period of “delayed diagnosis” – either the condition is not recognised, or a definitive diagnosis is not made due to the patient being considered “unlikely” to be experiencing the condition.
Pharmacists should refer anyone in this position for a second opinion, as delays in diagnosis can have significant impact on the progression of symptoms and infertility.
Jarrod McMaugh is a community pharmacy practitioner with Capital Chemist in the northern suburbs of Melbourne. He has extensive experience in developing and delivering professional services in the community pharmacy setting.
Sam Flood is a motivated pharmacy intern at Capital Chemist Coburg North, hailing from remote Tasmania. Sam completed a Bachelor of Pharmacy at UTAS. Although Sam is in the early stages of his career, he has had exposure to a variety of pharmacy settings, including extensive time working in opioid replacement therapy and forensic mental health.