EVRA ® - Contraceptive Patch

EVRA ® a drug based on ethinyl estradiol + norelgestromin

THERAPEUTIC GROUP: Hormonal contraceptives - Transdermal patch

IndicationsAction mechanismStudies and clinical effectiveness Usage and dosage instructionsWarnings Pregnancy and lactationInteractionsContraindicationsUndesirable effects

Indications EVRA ® - Contraceptive Patch

EVRA ® a hormonal contraceptive in the form of a transdermal patch.

Mechanism of action EVRA ® - Contraceptive Patch

EVRA ® an innovative contraceptive, characterized by a transdermal patch formulation, useful to reduce the errors connected to the classic oral hormonal contraception, often cause of unwanted pregnancies.

The advantages deriving from the implementation of these contraceptive methods are above all related to the decidedly increased compliance and to the pharmacokinetic properties that can significantly reduce the first-pass hepatic metabolism of both hormones, increasing bioavailability, thus allowing a significant reduction in dosages used.

The active ingredients present in EVRA ® mirror those of oral contraceptives, given the presence of ethinyl estradiol as estrogen and of norelgestromin, an active metabolite of norgestimate, as a progestin.

Consequently the contraceptive activity of this drug is carried out through:

Ovulation inhibition, mediated by negative feedback on the hypothalamic-pituitary axis, necessary to suppress endogenous gonadotropin secretion;
The induction of chemical-physical variations of the cervical mucus such as to make the ascent of the spermatozoa along the female genital tract more difficult.

In conclusion, the use of transdermal patches as contraceptives makes it possible to make the intake easier (one-week application), improve the compliance among the users, standardize the pharmacokinetic characteristics, allow a rapid suspension of contraception, without secondary effects and reduce the incidence of some adverse reactions thanks to the presence of a progestogen with very low androgenic activity.

Studies carried out and clinical efficacy

1. TRANSDERMIC CONTRACCEPTION AND THROMBOEMBOLIA

Dore DD, Norman H, Loughlin J, Seeger JD.

This discouraging study confirms the previous indications that the use of transdermal contraceptives would double the risk of developing embolic thrombus events compared to the common population.

2. EVRA'S SUCCESS AMONG ADOLESCENTS

The weekly frequency of administration and the easy application of EVRA have been particularly successful among adolescents, reducing the number of unwanted pregnancies especially in this age group

3. TRANSDERMIC PATCHES AND ACUTE CARDIOVASCULAR DISEASES

Study demonstrating that the use of transdermal contraceptive patches among young patients cannot be associated in any way with an increased incidence of infarction or acute myocardial ischemic events.

Method of use and dosage

EVRA ® 20 cm square transdermal patch containing 6mg of norelgestromin and 600mcg of ethinyl estradiol;

the formulation in transdermal patches significantly reduces the posological complexity typical of other oral hormonal contraceptives.

Starting the application of the first patch, the first day of menstruation, we will continue replacing it the following week to the same day (we will therefore be on the eighth day of the cycle) and the following week again, always on the same day (we will therefore be on the fifteenth day of cycle).

On the twenty-second day of the cycle, ie the fourth week, the intake will be suspended for seven days, during which suspension bleeding similar to menstruation should take place.

Once the week is over, it will resume with the previously described application scheme.

The patch should be applied to clean, lint-free skin, intact and preferably on the buttock, the abdomen, the upper external part of the arm or the upper part of the trunk, avoiding the breast.

It is necessary to avoid the application in the presence of redness, inflammation or skin diseases and repeat it in the case in which even a small part of the patch detaches from the skin, preserving however the initial application scheme.

In case of forgetfulness or detachments not warned it would be useful to consult your doctor, always using methods of contraception coverage.

Warnings EVRA ® - Contraceptive Patch

Like oral contraceptives, also the use of contraceptives for topical use must necessarily be preceded by a careful medical examination, useful to exclude the possible presence of conditions incompatible with the intake of this drug.

More precisely, the presence of risk factors such as smoking; diabetes; overweight; hypertension; heart valve defects or some heart rhythm disorders; superficial phlebitis (venous inflammation), varicose veins; migraine; depression; epilepsy; high levels of cholesterol and triglycerides in the blood, present or past, even in close family members; breast lumps; previous, in next family members, of breast cancer; liver or gallbladder disease; Crohn's disease or ulcerative colitis (chronic inflammatory bowel disease); systemic lupus erythematosus (pathology that affects the skin of the whole body); hemolytic-uremic syndrome (blood clotting disorder that causes renal failure); sickle cell disease; porphyria; Chloasma, present or previous, could significantly increase the risk of developing serious side effects such as thromboembolic, cardiovascular and neoplastic events.

In this regard, the doctor must assess the risk / benefit ratio together with the patient and opt for this type of contraception only in cases where this protocol can be managed and monitored through periodic checks.

PREGNANCY AND BREASTFEEDING

The use of EVRA is contraindicated in pregnancy and lactation, given the potential side effects of estrogen on the fetus.

Furthermore, the presence of ethinyl estradiol and norelgestromin appears to influence the physico-chemical properties of breast milk, extending this contraindication also to the subsequent breastfeeding period.

Interactions

Despite the topical route of administration, useful for significantly reducing first-pass hepatic metabolism, ethinyl estradiol and norelgestromin contained in EVRA ® are subject to the metabolizing action of cytochromial enzymes.

In this regard it is useful to remember how the concomitant intake of inducing active ingredients of the aforementioned enzymes such as primidone, phenytoin, barbiturates, carbamazepine, (used for the treatment of epilepsy), rifampicin (used for the treatment of tuberculosis ), ampicillin, tetracyclines, griseofulvin (antibiotics used to treat infectious diseases), ritonavir, modafinil and sometimes St. John's wort (hypericum perforatum), could cause a significant drop in the contraceptive activity of EVRA ®

It is therefore essential to always consult your doctor, possibly using contraceptive methods of coverage.

The estrogens and progestogens contained in this medicine could lead to a significant alteration of some laboratory values related to liver, thyroid, adrenal and renal function.

Contraindications EVRA ® - Contraceptive Patch

EVRA ® is contraindicated in case of current or previous venous thrombosis, stroke, hypertension, metabolic pathologies such as diabetes mellitus, hypertension and dyslipidemia, liver and kidney function changes, malignant pathologies, neuro-psychiatric disorders, motor disorders, undiagnosed gynecological disorders and in case of hypersensitivity to the active ingredient or to one of its excipients.

Undesirable effects - Side effects

The presence of a progestogen with very modest androgenic activity combined with topical medication, significantly reduces the risk of developing some adverse reactions characteristic of oral contraception.

In principle, the application of EVRA ® has been associated with high frequency to minor symptoms such as headache, nausea, and increased breast tension although post-marketing monitoring has shown in the patients predisposed the same side effects described for hormonal contraception oral.

Mood alterations, contact dermatitis and erythema, weight gain and water-based retention were the other side effects most frequently described during topical contraception, which were also accompanied less frequently by embolic thrombus events, blood glucose alterations and of the metabolic state, cardiovascular events, gallbladder lithiasis, pancreatitis and neoplastic pathologies.

It is useful to remember that these problems, observed with a modestly increased incidence compared to that of the common population, seem to occur mainly in predisposed individuals.