Dienogest belongs to the class of medications called progestins, medications that act like progesterones in the body. Progesterones are female hormones. They are produced by the body and are necessary along with other hormones for normal female sexual development and for the regulation of the menstrual cycle during childbearing years (males also have progesterones, but in low amounts).

Progestins reduce the effects of estrogen on tissues such as the endometrium (lining of the uterus) and the breast. By reducing the growth effect of estrogen on the endometrium, dienogest helps to reduce the pelvic pain experienced by women with endometriosis. Endometriosis is a condition where endometrium-like tissue is found outside the uterus, which causes chronic inflammation.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The recommended dose of dienogest is 2 mg taken by mouth once daily. This medication should be taken at the same time every day, if possible.

Take the medication continuously (every day) even if you are on your period. Once you have completed a pack of tablets, begin the new package on the next day. Dienogest is not intended to be used as birth control. Do not take a break from the medication.

Take dienogest with some liquid as needed. Dienogest may be taken with food or without food.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important that this medication be taken exactly as prescribed by your doctor.

If you miss a dose or if you vomit or have diarrhea within 3 to 4 hours of taking a tablet, take a dose as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Each white, round, biconvex, film-coated tablet embossed "2" on one side contains 2 mg dienogest. Nonmedicinal ingredients: cottonseed oil, hydroxypropylcellulose, hypromellose, lactose monohydrate, magnesium stearate, maize starch, povidone K 30, sodium starch glycolate (Type A), talc, and titanium dioxide.

Do not take dienogest if you:

• are allergic to dienogest or any ingredients of the medication
• are allergic to other progestins
• are or may be pregnant
• are breast-feeding
• have abnormal liver test results caused by liver disease or liver problems
• have a history of known or suspected estrogen-dependent tumours such as breast or uterine cancer
• have a history of migraine headaches with aura (classical migraine)
• have any eye lesions, vision loss, or other vision problems due to ophthalmic vascular disease (disease involving blood vessels of the eye)
• have circulation problems due to diabetes
• have or have had benign or malignant liver tumours
• have or have had a history of blood clots (e.g., in the legs or lungs), heart attack, stroke, or heart disease
• have undiagnosed abnormal vaginal bleeding

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• acne
• breast discomfort
• constipation
• decreased interest in sexual activity
• diarrhea
• difficulty sleeping
• dry eyes, skin or nails
• fluid retention (puffiness of hands, wrists, feet or ankles)
• gas (flatulence)
• hair loss
• headache
• hot flushes
• increased appetite
• increased migraine headache
• increased sensitivity to sun
• irritability
• nausea
• nervousness
• vomiting
• weakness
• weight gain

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• abdominal pain or discomfort
• anxiety
• back or bone pain
• breast lump
• breast pain or enlargement
• changes in vaginal bleeding (spotting, breakthrough bleeding, prolonged or heavier bleeding, or complete stoppage of menstrual periods)
• mood swings
• dry skin or patchy change of skin colour
• muscle spasms
• ringing in the ears
• rapid or pounding heartbeat
• signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• symptoms of a urinary tract infection (e.g., pain when urinating, urinating more often than usual, low back or flank pain)
• vaginal yeast infection

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a blood clot in blood vessels, such as sudden vision change or dizziness, chest pain, difficulty breathing, heart palpitations, pain and swelling in leg or arm

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Birth control: Dienogest is not a birth control pill. While taking this medication a non-hormonal method of birth control should be used, such as condoms or a diaphragm. Hormonal methods of birth control (e.g., birth control pills, patches, rings) should not be used in combination with dienogest.

Blood clots: Dienogest may increase the risk of developing blood clots in the lungs and legs. This risk also increases with age, a personal or family history of blood clots, smoking, and obesity. The risk of blood clots is also increased if you are immobilized for prolonged periods and with major surgery. If possible, this medication should be stopped 4 weeks before major surgery. Talk about the risk of blood clots with your doctor.

Breast cancer: Some studies have shown that the risk of developing breast cancer does not appear to be increased by using progestin-only medication such as dienogest. However, more studies are needed to confirm that there is no increased risk. The most significant risk factors for breast cancer are increasing age and a strong history of breast cancer in the family (sister or mother).

Let your doctor know if you notice any breast lumps. Talk to your doctor about regular breast exams.

Cigarette smoking: Cigarette smoking increases the risk of serious side effects on the heart and blood vessels. This risk increases with age and becomes significant after age 35. Do not smoke if you use this medication, especially if you are over 35. Consider stopping smoking before taking this medication. If you smoke, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Depression: Hormones, such as estrogen and progestins, have been known to cause mood swings and symptoms of depression. If you have depression or a history of depression, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

If you experience symptoms of depression such as poor concentration, changes in weight, changes in sleep, decreased interest in activities, or notice them in a family member who is taking this medication contact your doctor as soon as possible.

Diabetes: As with other progestins, dienogest may cause changes in blood glucose control. Women with diabetes should monitor their blood glucose closely to detect any changes in blood glucose control that sometimes occur with use of hormones. If you have diabetes or are at risk for developing diabetes, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you experience symptoms of high blood glucose such as increased need to urinate at night, a fruity odour to your breath or wounds that require longer than normal to heal, contact your doctor.

Irregular menstruation: Irregular menstrual patterns are common among women taking progestin like dienogest. If you notice changes in your usual menstrual patterns, check with your doctor. If you go a prolonged time without bleeding, you should have a pregnancy test.

Liver disease: Dienogest may affect liver function. This medication is not recommended for people with liver problems. If you have a history of liver problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Osteoporosis: Dienogest may decrease estrogen levels in the body and increase the risk of osteoporosis (a condition where parts of the bone become weak and prone to fracture). When this medication is taken by adolescents, it may cause a decrease in the development of bones and increase the risk of developing osteoporosis. If you are at an increased risk of osteoporosis, your doctor will monitor you while you are taking dienogest.

Pregnancy: This medication should not be used during pregnancy. If you become pregnant while taking this medication, contact your doctor immediately. People who become pregnant while taking dienogest are at a slightly increased risk of having an ectopic pregnancy (a pregnancy where the embryo develops outside the uterus).

Breast-feeding: It is not known if dienogest passes into breast milk. This medication should not be taken while breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for females who have not begun to menstruate.

There may be an interaction between dienogest and any of the following:

• aprepitant
• azole antifungals (e.g., ketoconazole, itraconazole, voriconazole)
• bosentan
• bromocriptine
• calcium channel blockers (e.g., diltiazem, nifedipine, verapamil)
• colestipol
• cobicistat
• darolutamide
• deferasirox
• dexamethasone
• diabetes medications (e.g., glyburide, insulin, linagliptin, metformin, rosiglitazone)
• echinacea
• elagolix
• enzalutamide
• flibanserin
• gingko
• HIV non-nucleoside reverse transcriptase inhibitors (NNRTIs; e.g., efavirenz, etravirine)
• HIV protease inhibitors (e.g., atazanavir, ritonavir)
• hormonal birth control (e.g., birth control pills, patches, rings)
• macrolide antibiotics (e.g., clarithromycin, erythromycin)
• mifepristone
• mycophenolate
• mitotane
• modafinil
• nirmatrelvir
• perampanel
• phenobarbital
• pitolisant
• protein kinase inhibitors (e.g., ceritinib, dabrafenib)
• octreotide
• rifabutin
• rifampin
• rivaroxaban
• sarilumab
• satralizumab
• St. John's wort
• seizure medications (e.g., carbamazepine, phenytoin, primidone, topiramate)
• tecovirimat
• telotristat
• thalidomide
• tocilizumab
• tranexamic acid
• ulipristal
• warfarin

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.