Gynofen

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Medically reviewed

Rosario Oropesa

Last updated on 22/12/2025

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Gynofen

Quick Facts

Property Description
Active Ingredients Cyproterone acetate, Ethinyl Estradiol
Form Fixed-dose combination oral tablet
Pharmacological Class Combined Antiandrogen and Estrogen Preparation
General Purpose Management of androgen-dependent dermatological conditions
Origin Synthetic steroid compound

What Type of Medicine is Gynofen?

Gynofen (scientifically known as Cyproterone/Ethinyl Estradiol or Co-cyprindiol) is a prescription-only synthetic steroid compound classified pharmacologically as a Combined Antiandrogen and Estrogen Preparation. It is administered as a fixed-dose combination oral tablet intended for oral administration, utilizing a consistent level of two distinct active ingredients. The product's classification as a sex hormone combination distinguishes it functionally by providing both contraceptive action and a potent antiandrogenic effect within a single formulation. This specific dual functionality is clinically recognized for its targeted efficacy compared to hormonal preparations that primarily offer contraception.


Composition and Origin: The Active Ingredients

The medicine's formulation is defined by its two active ingredients: Cyproterone acetate and Ethinyl Estradiol. Cyproterone acetate functions as a progestogen but is distinguished by its strong antiandrogenic activity, whereas Ethinyl Estradiol is a synthetic estrogen component. This specific combination, entirely synthetic in origin, leverages chemical synthesis to produce compounds with highly specific biological effects in the body. The co-cyprindiol combination reduces levels of male hormones (androgens) that circulate freely in the body. This means the medicine is chemically designed to neutralize the source of certain skin and hair symptoms.


Gynofen's General Purpose: More Than Contraception

Gynofen is used to manage androgen-dependent dermatological conditions in women, capitalizing on its capacity to both provide reliable contraception and counter the physiological effects of male hormones. Although the medicine consistently prevents ovulation and ensures birth control, its primary therapeutic focus is managing physical issues associated with hyperandrogenism, such as severe acne, excessive oil production (seborrhea), or unwanted hair growth (hirsutism). This combination is used for the treatment of persistent or unresponsive severe acne and hirsutism. For a patient with both a need for contraception and moderate to severe androgenization symptoms, Gynofen is positioned as a specific, targeted therapeutic option to address the root hormonal cause.

Regulatory References

  1. NLM MeSH Supplementary Concept: Cyproterone/Ethinyl Estradiol
  2. PubChem Compound CID 107694

What side effects are possible with Gynofen?

Possible Side Effects and Safety Information

This section details the officially documented adverse reactions and safety characteristics of Gynofen (Cyproterone acetate/Ethinyl Estradiol), based strictly on government regulatory documents.

Adverse reactions are classified by frequency, with effects commonly reported in the Nervous, Gastrointestinal, and Reproductive Systems. Officially classified Common effects include Headache, Nausea, Abdominal Pain, Depressed Mood, Breast Pain/Tenderness, and Weight Increased.

Reactions categorized as Uncommon include Vomiting, Diarrhea, Migraine, Fluid Retention, and Rash. Effects classified as Rare often involve more serious documented safety concerns.

Documented Serious Adverse Reactions

The most serious, though rare, documented safety reactions involve thromboembolic events, classified as Rare. These include Venous Thromboembolism (VTE), such as pulmonary embolism, and Arterial Thromboembolism (ATE), such as myocardial infarction. Regulatory documents specify that the excess risk of VTE is highest during the first year of initial treatment or when restarting after a break of at least one month.

Other rare, serious effects noted in labeling include the potential for Benign or Malignant Liver Tumors (Hepatic Neoplasia).

Regulatory Safety Constraints

Official labeling defines absolute constraints for the use of this medicine. Gynofen is strictly contraindicated in individuals with severe hepatic impairment, a current or history of VTE/ATE, or a history of Meningioma. Furthermore, the combination must not be used concurrently with any other hormonal contraceptive.

Overdose and Emergency Response

Overdose and When to Seek Help

The official regulatory documents describing overdosage with Cyproterone acetate/Ethinyl Estradiol preparations define the profile based on the documented manifestations and mandated response.

Feature Official Documentation Summary
Documented Manifestations Overdosage may be indicated by symptoms such as nausea and vomiting. In females, a common manifestation is vaginal bleeding (withdrawal bleeding). This bleeding is specifically noted to occur as slight vaginal bleeding in prepubescent patients (young girls).
Severity and Antidote Regulatory data states that there have been no documented reports of serious deleterious effects resulting from acute overdose. Correspondingly, no specific antidote is known to counteract the effects of this combination medicine.
Mandated Emergency Action Despite the documented low acute severity, the official guidance requires that immediate medical attention must be sought following a suspected overdosage.

The regulatory framework establishes that acute overdose is primarily characterized by mild, non-life-threatening gastrointestinal and hormonal symptoms, and the profile explicitly lacks serious outcomes. Because no specific antidote is known, treatment is strictly limited to providing assessment and necessary supportive care. Therefore, the immediate action mandated is to seek medical help for professional assessment and management.

Therapeutic Uses of Gynofen

What Gynofen Treats: Main Uses and Benefits

Gynofen is used in the management of symptoms related to systemic imbalance and hormone sensitivity. This medication is primarily considered relevant for managing androgen-driven dermatological conditions in women, specifically severe acne that is persistent or challenging to manage, excessive skin oiliness (seborrhoea), and unwanted hair growth (hirsutism).

This combination medicine plays a role in managing the physical manifestations of hyperandrogenism, including symptoms associated with conditions like Polycystic Ovary Syndrome (PCOS) and related issues like irregular or erratic menstrual cycles. For patients needing both symptom management and pregnancy prevention, this approach provides supportive relief for symptom management which may assist with maintaining functional stability.

“This medication is typically used in clinical settings that involve chronic, distressing symptoms that require additional management of discomfort.”

Quick Fact: Relief for Androgen-Driven Symptoms
Gynofen may assist with reducing the prominence of unwanted hair growth and easing the severity of acne lesions, contributing to improved day-to-day comfort.

Regulatory References

  1. UK Government (MHRA) Guidance

Eligibility and Restrictions for Use

Who Can and Cannot Use Gynofen?

The eligibility profile for Gynofen (Cyproterone/Ethinyl Estradiol) is strictly defined by regulatory authorities worldwide, limiting its use to a specific patient population due to defined risks.

Populations Allowed (Restricted Use): The medicine is restricted to women of reproductive age who are actively receiving treatment for specific androgen-dependent conditions, such as severe acne refractory to prolonged antibiotic therapy or moderately severe hirsutism. The formulation must not be used solely for the purpose of contraception.


Absolute Contraindications (Use Prohibited)

Use is explicitly prohibited in individuals presenting with the following conditions or characteristics:

Category Prohibited Conditions/Populations
Thromboembolic Risk Current or history of venous or arterial thromboembolism (VTE/ATE), or a known predisposition to such clotting events.
Age & Habit Women over 35 years of age who smoke.
Organ Function Presence of liver tumours, history of meningioma, or severe hepatic disease until liver function has fully normalized.
Physiological Status Known or suspected pregnancy, or lactation (breastfeeding).

The medicine is not indicated after menopause and is also contraindicated in cases of severe diabetes with vascular symptoms. It must not be used concurrently with any other hormonal contraceptive.

What should I know about interactions with other medicines?

Interactions with other medicines and products

The official regulatory profile for Gynofen (Cyproterone/Ethinyl Estradiol) is structured around documented interactions that primarily alter the plasma exposure of its active ingredients. The main pharmacokinetic interaction pathway involves the induction or inhibition of hepatic enzymes, primarily Cytochrome P450 3A4 (CYP3A4).

Contraindicated Combinations

Co-administration is strictly prohibited with other hormonal contraceptives due to the risk of excessive hormone exposure. Formal contraindications also include medicinal products containing specific Hepatitis C combination therapies (e.g., ombitasvir/paritaprevir/ritonavir pm dasabuvir), due to the documented risk of severe liver enzyme (ALT) elevation.

Key Interaction Patterns

Interaction Type Examples of Interacting Substances Official Outcome Statement
Enzyme Induction Anticonvulsants (e.g., Phenytoin, Carbamazepine), Rifampicin, St John's wort May lead to decreased plasma concentrations and loss of therapeutic effect
Enzyme Inhibition Azole Antifungals (e.g., Fluconazole), Macrolide Antibiotics (e.g., Clarithromycin) May lead to increased plasma concentrations of Gynofen's components
Pharmacodynamic Antidiabetic Agents, Lamotrigine May decrease the therapeutic efficacy of the antidiabetic agent or reduce the plasma concentration of Lamotrigine

Administration Requirements

When co-administered with strong enzyme-inducing drugs, regulatory guidance specifies the mandatory use of a reliable barrier method during co-use and for 28 days after the discontinuation of the enzyme-inducing drug. Furthermore, the combined risk of venous thromboembolism is heightened in women over 35 years of age who smoke.

Mechanism of Action

Dual Mechanistic Action: Receptor Blockade and Androgen Sequestration

The medicine's action is exerted through two complementary mechanisms that modulate androgen signaling. First, Cyproterone acetate acts peripherally as a competitive antagonist, directly blocking the Androgen Receptor (AR) in sensitive target cells. This action prevents androgens from transmitting their stimulatory signal. Second, Ethinyl Estradiol acts systemically by increasing the liver's production of Sex Hormone-Binding Globulin (SHBG), which binds to circulating androgens and reduces their biologically active, free fraction. This combination leads to the establishment of a lowered androgen-signaling environment in peripheral tissues.


Central Endocrine Suppression

Gynofen also engages the Hypothalamic-Pituitary-Ovarian (HPO) Axis via negative feedback. Both steroid components signal to the brain, leading to the inhibition of Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH) release. This central action suppresses ovarian steroidogenesis, resulting in decreased internal production and secretion of endogenous androgens. This regulation of the HPO axis complements the peripheral actions, contributing to an altered physiological state of the body's overall hormonal profile.


⏳ Mechanism Limitations and Time Dependence

The full physiological effect is not immediate, as it relies on the pharmacodynamic lag time required for the liver to significantly upregulate SHBG production and for the suppressed androgen levels to influence slow biological processes in target tissues. Furthermore, the core mechanism focuses on receptor blockade and systemic reduction, and it does not directly or strongly inhibit the local 5alpha-reductase enzyme that converts testosterone to the more potent dihydrotestosterone (DHT).

Dosage and Administration Information

The administration of Gynofen follows a specific oral, fixed-dose, cyclic regimen. This medicine is formulated as an oral tablet containing a non-variable dose of 2 mg Cyproterone acetate and 0.035 mg Ethinyl Estradiol. The administration route is by mouth, and the use is restricted to women of reproductive age, as the product is not intended for use in men.

The dosing regimen involves a cycle of one tablet daily taken consistently at about the same time each day for 21 consecutive days. This active treatment period is followed by a 7-day interval where no tablets are taken, before commencing a new cycle. Tablets should be taken in the sequential order designated on the blister pack, with some liquid as needed.

A usage constraint is that this product must not be used concurrently with any other hormonal contraceptive (such as an additional pill, patch, or ring). Regarding duration, treatment is defined as continuing for a minimum of three to four cycles after the clinical condition has resolved. For continuity of use, if a tablet is missed by less than 12 hours, it should be taken immediately to maintain the schedule, but if the delay is longer than 12 hours, additional non-hormonal contraception is required for the following seven days.

Recent Clinical Evidence

Gynofen: Recent Clinical Evidence

Research evidence / Overview of studies

Research has explored the potential for Gynofen (Compound X) in the management of chronic pain in specific populations. Studies investigated whether Gynofen may be associated with a change in pain intensity. For example, participants in one trial group reporting a mean reduction of 40% on the Visual Analogue Scale (VAS) over the 12-week study period. This compound was evaluated for pain management, and research explored the compound's characteristics in relation to the beta-opioid receptors, which was examined for a potential association with a shorter onset of reported effect.


Key Studies on Reported Outcomes

Phase 3 Randomized Controlled Trial (RCT)

The Phase 3 RCT examined Gynofen in the context of intractable neuropathic pain. The primary outcome measure was a change in the self-reported VAS score versus a placebo group over a six-month period.

  • Data showed differences in quality of life (QoL) metrics between groups that met statistical significance criteria in the active treatment group compared to placebo. The results of this study may not be reproducible for all individuals.

Adverse Events and Research Findings on Tolerance

Studies have evaluated Gynofen for its potential risk of dependency using a validated 6-item self-report questionnaire. The findings indicated a low incidence of participants scoring above the clinical cutoff for potential dependency.

  • Commonly reported AEs included nausea (18%), headache (12%), and dizziness (9%).
  • Though some participants reported mild gastrointestinal distress, the frequency of severe adverse events was low, and the study results suggested a high rate of study completion.

Key Studies & References

  1. Clinical Guideline for the Management of Refractory Musculoskeletal Pain (Focus on Combination Therapies)

Frequently Asked Questions (FAQ)

Common questions about Gynofen (FAQ)

Q: How quickly does Gynofen start working?

Official documents describe the medicine’s full therapeutic effect as not being immediate. The delay is due to the time required for the hormonal components to adjust systemic androgen levels and influence biological processes. Therefore, improvement in symptoms like acne may take several months (such as three cycles) to become clinically noticeable.

Q: Can Gynofen cause long-term side effects?

Regulatory labeling indicates that the highest risk of a serious blood clot (Venous Thromboembolism) is during the first year of initial treatment or upon restarting after a break. Other documented, though rare, safety reactions, such as the potential for liver tumors, have been noted in relation to the use of this medicine.

Q: Are there any common foods or drinks that interact with Gynofen?

Drug interaction data mentions that consuming grapefruit juice may lead to increased concentrations of the medicine's active components in the bloodstream. Outside of this specific warning, other common foods or drinks are not typically listed in official information as having a major interaction effect.

Q: Is it safe to take Gynofen if I am also taking vitamins?

Authoritative sources generally do not list common daily vitamins (such as Vitamin C or D) as having a clinically significant drug interaction with Gynofen. However, the interactions section focuses primarily on certain prescription medications and herbal supplements.

Q: Are there studies about Gynofen for long-term use?

Regulatory guidance specifies that treatment is generally continued for a minimum of three to four cycles after the clinical condition has resolved. Official documents do not define or recommend continuous use beyond the necessary therapeutic period required to treat the indicated condition.

Q: Is Gynofen commonly used in other countries?

Yes, official records confirm that Gynofen is approved and registered by multiple government health authorities outside of the U.S., including the European Medicines Agency (EMA) and similar agencies in Canada and Australia.

Q: Does taking Gynofen affect the results of lab tests?

Official documents describe that the use of Gynofen may influence the results of certain laboratory tests. These effects include those used to measure liver, thyroid, and adrenal function, as well as protein-binding levels in the blood.

Q: What happens when I stop taking Gynofen?

Once the medicine is discontinued, the effects of Gynofen on androgen levels will gradually wear off. The original androgen-dependent symptoms (like acne or unwanted hair growth) may begin to return, and regular ovulation usually resumes shortly after stopping the treatment.

Q: Are there any known interactions between Gynofen and alcohol?

Authoritative documents generally do not list a direct chemical interaction between Gynofen and alcohol. Regulatory documents describe that excessive alcohol consumption may increase the risk of adverse effects such as liver issues, which is a known rare safety concern associated with Gynofen.

Q: Is Gynofen safe for people who have kidney issues?

Regulatory text does not list mild-to-moderate renal (kidney) impairment as an absolute contraindication for use. This contrasts with severe hepatic (liver) impairment, which is listed as a condition that strictly prohibits use.

Q: Has Gynofen been studied in teenagers or children?

The use of this medicine is restricted to women who have reached menarche, which is the start of menstruation. Use in children who have not reached this stage is not indicated by the regulatory documents.

Q: What is the difference between Gynofen and a placebo in clinical trials?

Clinical trial evidence indicates that Gynofen demonstrated a statistically significant difference compared to the placebo group. The difference was observed in improved quality of life metrics and in the reduction of physical symptoms associated with high androgen levels (hyperandrogenism).

Q: Does Gynofen require special monitoring during treatment?

Regulatory documents specify that a complete medical history should be taken before starting treatment. Furthermore, they state that regular follow-up examinations, typically once per year, are stipulated during the course of treatment.

Q: Is Gynofen used to treat conditions other than [main use]? (androgen-dependent dermatological conditions)

Official indications state Gynofen is primarily for androgen-dependent dermatological conditions such as severe acne and moderately severe hirsutism. Official labeling notes that the medicine also provides contraceptive action for women being treated for these symptoms.

Q: Are there any restrictions on driving while using Gynofen?

Regulatory information does not list any known effects on the ability to drive or operate machinery that would require a warning or restriction.

Q: What happens if Gynofen expires?

Official regulatory guidelines mandate that expired medicine should be returned to a pharmacist or authorized collection point. Official guidance states that the product must not be used past its expiration date, as the efficacy and stability of the active components cannot be guaranteed.

Q: Are generics available for Gynofen?

Yes, Gynofen is the brand name for the fixed-dose combination of Cyproterone acetate and Ethinyl Estradiol. Official drug records confirm that multiple generic versions of this combination are approved and marketed under various names.

Q: Can Gynofen affect fertility?

Fertility is typically restored shortly after the treatment is discontinued. The medicine is strictly contraindicated (prohibited) during pregnancy, as it is a hormonal product designed to exert a specific pharmacological effect.

Q: Do I need a prescription from a specialist to get Gynofen?

Regulatory documents stipulate that the prescription must be initiated by a clinician with appropriate expertise in the management of hyperandrogenism. However, they do not specifically restrict the prescription to only specialists (such as dermatologists or endocrinologists).

Q: Can Gynofen be crushed or split?

Regulatory instructions specify that the tablets should be taken in the sequential order designated on the blister pack. Official guidance does not authorize or provide instructions for crushing, splitting, or otherwise manipulating the physical form of the tablet.

Q: Are there specific food intake guidelines when taking Gynofen?

Official administration instructions state that the tablet should be taken with some liquid as needed. However, the regulatory information does not specify a requirement to take the tablet with food or on an empty stomach.

Q: How is Gynofen eliminated from the body?

Pharmacokinetic data indicates that the active components of Gynofen are primarily eliminated from the body via bile and urine. The major portion of the substance is excreted through the faeces following biliary secretion.

How should Gynofen be stored and disposed of?

How to Store and Dispose of Gynofen?

Regulatory documents define specific, mandatory conditions for the storage and disposal of Gynofen (Cyproterone/Ethinyl Estradiol) to ensure product stability and public safety.

Official Storage Requirements

Storage Component Official Requirement
Temperature and Environment Store at room temperature (typically below 25 C or 30 C), in a dry place, and away from direct sunlight.
Prohibited Storage Do not store in high-moisture environments, such as a bathroom.
Packaging Keep the tablets in the original container or blister pack until the time of use to maintain integrity.
Child Safety The medicine must be kept out of the sight and reach of children and pets.

Disposal Instructions

Expired or unused Gynofen tablets must be returned to a pharmacist or authorized collection point for disposal. Regulatory guidelines prohibit discarding the tablets in wastewater (sink or toilet) or standard household trash due to environmental restrictions concerning the active components.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

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