Implanon (Implant) Instructions for Use

ATC Code

G03AC08 (Etonogestrel)

Active Substance

Etonogestrel (Rec.INN registered by WHO)

Clinical-Pharmacological Group

Hormonal contraceptive for transdermal application

Pharmacotherapeutic Group

Contraceptive agent

Pharmacological Action

Progestin. Etonogestrel is a biologically active metabolite of desogestrel, a progestin widely used as an oral contraceptive hormonal agent. Structurally, it is a derivative of 19-nortestosterone and binds with high affinity to progesterone receptors in target organs. The contraceptive effect of etonogestrel is mainly achieved by suppressing ovulation. No ovulations were observed during the first 2 years of use, and they occurred only rarely during the third year.

In addition to suppressing ovulation, Etonogestrel also causes an increase in the viscosity of cervical mucus, which prevents the passage of spermatozoa. Clinical studies were conducted in women aged 18-40 years.

The contraceptive effect of etonogestrel is reversible. Although Etonogestrel suppresses ovulation, ovarian activity is not completely suppressed.

Etonogestrel does not affect changes in bone mineral density and lipid metabolism.

Pharmacokinetics

Etonogestrel is characterized by a high degree of binding to plasma proteins: about 32% to sex hormone-binding globulin and 66% to albumin. It is metabolized with the participation of the CYP3A4 isoenzyme. It is excreted in urine and feces as metabolites and unchanged substance. T_1/2 is 25-30 hours. Etonogestrel penetrates into breast milk.

Indications

Hormonal contraception.

ICD codes

Dosage Regimen

Insert one Implanon subdermally into the inner side of the non-dominant upper arm approximately 6-8 cm above the medial epicondyle.

Perform insertion between day 1 and day 5 of the menstrual cycle, even if the woman is still bleeding.

Ensure the implant is inserted correctly and subdermally to facilitate subsequent removal.

Confirm the presence of the implant in the arm by palpation immediately after the procedure.

Provide the woman with a user card containing the date of insertion and the scheduled removal date.

The implant provides continuous contraception for up to three years.

Remove the implant by the end of the third year of use; a new implant may be inserted at the time of removal if continued contraception is desired.

If insertion occurs after day 5 of the menstrual cycle, advise the use of a barrier method of contraception for the next 7 days.

Insert the implant immediately after a first-trimester abortion or miscarriage.

Insert the implant no earlier than 21-28 days postpartum in non-breastfeeding women.

Insertion can be considered in breastfeeding women after the fourth postpartum week.

Remove the implant if the woman develops a contraindication during use, such as thrombosis or severe liver disease.

Instruct the woman to report for immediate removal if she experiences persistent, clinically significant headaches or any symptoms of thrombosis.

Adverse Reactions

The connection of the adverse effects listed below with the use of etonogestrel in the form of an implant has neither been confirmed nor refuted.

From the reproductive system and mammary glands, changes in the nature of menstrual bleeding are possible (including changes in frequency, intensity, or duration of bleeding); very often (≥1/10) – breast tenderness, breast pain, irregular menstruation; often (≥1/100, <1/10) – dysmenorrhea, ovarian cyst; infrequently (≥1/1000, <1/100) – vulvovaginal discomfort, galactorrhea, breast enlargement, vulvovaginal itching; isolated reports – ectopic pregnancy.

Infections and infestations very often (≥1/10) – vaginal infection (vulvovaginitis); infrequently (≥1/1000, <1/100) – pharyngitis, rhinitis, urinary tract infection (urethritis, cystitis).

From the nervous system very often (≥1/10) – headache; often (≥1/100, <1/10) – dizziness; infrequently (≥1/1000, <1/100) – migraine, somnolence.

From the psyche often (≥1/100, <1/10) – emotional lability, depression, nervousness, decreased libido; infrequently (≥1/1000, <1/100) – anxiety, insomnia.

From metabolism very often (≥1/10) – weight increased; often (≥1/100, <1/10) – increased appetite, weight decreased.

From the skin very often (≥1/10) – acne; often (≥1/100, <1/10) – alopecia; infrequently (≥1/1000, <1/100) – hirsutism, rash, pruritus; rarely – seborrhea.

From the digestive system often (≥1/100, <1/10) – abdominal pain, nausea, abdominal distension; infrequently (≥1/1000, <1/100) – vomiting, constipation, diarrhea.

From the musculoskeletal system infrequently (≥1/1000, <1/100) – back pain, arthralgia, myalgia, musculoskeletal pain.

From the urinary system infrequently (≥1/1000, <1/100) – dysuria.

Allergic reactions possible – anaphylactic reactions, urticaria and angioedema (or its more severe course) and/or more severe course of hereditary angioedema.

General reactions often (≥1/100, <1/10) – fatigue, influenza-like illness, pain.

Other often (≥1/100, <1/10) – hot flush; infrequently (≥1/1000, <1/100) – dysuria; rarely – clinically significant increase in blood pressure.

In women using hormonal contraceptive agents, the following are possible: venous thromboembolism (VTE, deep vein thrombosis and pulmonary embolism); arterial thromboembolism; hormone-dependent tumors (liver tumors, breast cancer); chloasma; jaundice and/or pruritus associated with cholestasis; cholelithiasis; porphyria; systemic lupus erythematosus; hemolytic-uremic syndrome; Sydenham’s chorea; herpes of pregnancy; hearing loss associated with otosclerosis.

Contraindications

Pregnancy (including suspected); current or history of thrombosis (arterial and venous) and thromboembolism (including thrombosis, deep vein thrombophlebitis, pulmonary embolism, myocardial infarction, ischemic or hemorrhagic cerebrovascular disorders); presence of antiphospholipid antibodies; migraine with focal neurological symptoms; breast cancer (including history); established or suspected malignant hormone-dependent tumors; current or history of benign or malignant liver tumors; severe forms of liver disease (until liver function tests normalize), including jaundice; congenital hyperbilirubinemias (including history); uncontrolled arterial hypertension; childhood; vaginal bleeding of unknown etiology; hypersensitivity to etonogestrel.

Use in Pregnancy and Lactation

Contraindicated for use during pregnancy. Preclinical studies have found that very high doses of progestogenic compounds can cause masculinization of female fetuses.

It is known that a small amount of etonogestrel is excreted in breast milk. Based on available data, the use of etonogestrel in the form of an implant during breastfeeding is possible, but only under medical supervision for the development and growth of the breastfed infant.

Special Precautions

Etonogestrel in the form of an implant should be used with caution and after a thorough assessment of the benefit/possible risk ratio in each specific case in the presence of any of the following conditions or risk factors: prolonged immobilization caused by surgery or other reasons; conditions preceding thrombosis (including transient ischemic attacks, angina, complicated valvular heart disease, atrial fibrillation, major trauma); persistent arterial hypertension; diabetes mellitus, including diabetes mellitus with diabetic angiopathy; hereditary or acquired predisposition to arterial thrombosis, including protein C deficiency, protein S deficiency, antithrombin III deficiency; mild to moderate liver diseases with normal liver function tests; therapy with anticoagulants; severe depression.

In case of acute or exacerbation of chronic liver diseases, a woman should consult a specialist for examination and consultation.

Epidemiological studies have established a link between the use of combined oral contraceptives and an increased incidence of venous thromboembolism (deep vein thrombosis and pulmonary embolism). Although the clinical significance of these results for etonogestrel (a biologically active metabolite of desogestrel) used as a contraceptive hormonal agent in the absence of an estrogen component is unknown, the implant should be removed in case of thrombosis.

Although progestins can affect peripheral tissue insulin resistance and glucose tolerance, there is no confirmation that it is necessary to change the therapeutic regimen in patients with diabetes using progestin-only contraceptive hormonal agents. Nevertheless, women with diabetes should be under close observation throughout the period of use of progestin-only contraceptive hormonal agents.

Periodic examinations of women undergoing therapy for hyperlipidemia should be carried out. Some progestins may increase LDL levels and worsen hyperlipidemia control.

Chloasma may sometimes occur, especially in women with a history of chloasma of pregnancy. Women predisposed to chloasma should avoid exposure to sunlight or ultraviolet radiation during the use of etonogestrel.

Although Etonogestrel suppresses ovulation, in the case of amenorrhea or abdominal pain in a woman, ectopic pregnancy should be considered in the differential diagnosis.

There are reports of the following conditions occurring both during pregnancy and during the use of sex steroid hormones, but a connection with the use of progestins has not been established: jaundice and/or pruritus associated with cholestasis; formation of gallstones; porphyria; systemic lupus erythematosus; hemolytic-uremic syndrome; Sydenham’s chorea; herpes of pregnancy; hearing loss associated with otosclerosis and (hereditary) angioedema.

The use of etonogestrel is not indicated before the onset of menarche (first menstruation).

Influence on the ability to drive vehicles and operate machinery

Etonogestrel may cause dizziness. Therefore, the woman should be warned that if dizziness occurs, she should not drive a car or operate complex machinery.

Drug Interactions

Interactions between hormonal contraceptives and other medicinal products may lead to breakthrough bleeding and/or a decrease in the contraceptive effect. No specific studies on interactions with etonogestrel have been conducted.

Storage Conditions

Store at 2°C (36°F) to 30°C (86°F). Keep in original packaging, protected from light. Keep out of reach of children.

Dispensing Status

Rx Only

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.