Clomifeno

Quick links to important sections

Clomifeno

Medically reviewed

Laura Arias

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 Clomifeno

What is Clomifeno?

Clomifeno (commonly known as clomiphene citrate) is an oral medication classified as a selective estrogen receptor modulator (SERM). It is primarily used in reproductive medicine to assist individuals who experience difficulties with ovulation.

Mechanism of Action

The medication works by interacting with estrogen receptors in the brain, specifically within the hypothalamus and pituitary gland. By blocking the normal feedback of estrogen, clomifeno tricks the body into perceiving that estrogen levels are low. In response, the pituitary gland increases the production of two essential hormones:

  • Follicle-Stimulating Hormone (FSH): Stimulates the growth and maturation of ovarian follicles.
  • Luteinizing Hormone (LH): Triggers the release of a mature egg during ovulation.

Primary Uses

Clomifeno is typically indicated for the treatment of ovulatory dysfunction in those seeking to achieve pregnancy. It is frequently utilized in the following contexts:

  • Anovulation: For individuals who do not release an egg during their monthly cycle.
  • Oligovulation: For individuals who ovulate irregularly.
  • Polycystic Ovary Syndrome (PCOS): It is a common first-line option for inducing ovulation in patients with this hormonal condition.

By encouraging the development of one or more mature follicles, the medication increases the physiological probability of conception through natural intercourse or intrauterine insemination.

Regulatory References

  1. Clomiphene: MedlinePlus Drug Information

What side effects are possible with Clomifeno?

The safety profile of Clomifeno (Clomifene citrate) is structured by regulatory agencies to describe documented adverse reactions and specific usage restrictions. Side effects are classified by frequency and the body system affected, primarily grouped into System-Organ Classes (SOC) that include the Reproductive System, Nervous System, Gastrointestinal system, and Ocular disorders.

Common adverse reactions typically include vasomotor flushing (hot flashes), headache, nausea, and ovarian enlargement or discomfort. Reactions reported in fewer than 1% of clinical trial patients include effects such as depression, insomnia, dizziness, and changes to skin and hair.

The regulatory documents specifically detail serious adverse reactions. These include Ovarian Hyperstimulation Syndrome (OHSS), which can involve severe systemic complications. Other serious documented risks are thromboembolic events and, in rare instances, irreversible visual disturbances. Furthermore, the safety profile notes a potential association between prolonged use (one year or more) and the risk of ovarian tumour development.

Safety-related restrictions define the boundaries of use. Clomifeno is formally contraindicated during pregnancy and in patients with active liver disease, abnormal uterine bleeding of undetermined origin, or an organic intracranial lesion. The medication's use also carries a documented increased chance of multiple pregnancy and ectopic pregnancy. Visual symptoms may increase in incidence with higher dosage or duration of therapy.

Overdose and Emergency Response

Overdose and when to seek help

Official regulatory documents define the overdose profile of Clomifene citrate by detailing documented clinical signs, severe potential outcomes, and regulator-mandated emergency actions.


Documented Manifestations and Complications

Symptoms and signs listed in prescribing information as manifestations of overdose include nausea, vomiting, and vasomotor flushes (hot flashes). Overexposure may also present with visual disturbance, specifically scotomata (spots or flashes), and localized effects such as ovarian enlargement with associated pelvic and abdominal pain.

The regulatory profile identifies Ovarian Hyperstimulation Syndrome (OHSS) as a potentially life-threatening complication associated with therapy that may progress rapidly. Additionally, irreversible visual disturbance is noted as a risk factor linked to increased total dosage or duration of use.


Emergency Actions and Supportive Care

In the event of suspected overexposure, official guidance mandates that individuals seek immediate medical attention or contact a poison control center or emergency room at once. If the patient reports severe visual symptoms, the product must be discontinued immediately.

Overdose management requires the employment of appropriate supportive measures, including procedures such as gastrointestinal decontamination and gastric lavage. Regulatory documentation specifies that there is no specific antidote known for Clomifene citrate overdose.

Therapeutic Uses of Clomifeno

What Clomifeno Treats: Main Uses and Benefits

Clomifeno (Clomiphene citrate) is primarily used in reproductive medicine to manage symptomatic discomfort associated with ovulatory issues and to provide supportive management for male infertility. It is applied across domains where additional symptomatic support is needed.

Its main therapeutic applications include ovulatory dysfunction (including certain types of Polycystic Ovary Syndrome or secondary amenorrhea) and, in specific cases, supportive management for oligospermia (low sperm count) in males.


Support for Ovulatory and Hormonal Symptom Clusters

Clomifeno is commonly used across conditions presenting with episodic or fluctuating manifestations, such as when the lack of regular ovulation creates noticeable interference with daily stability. The therapeutic use helps address symptom clusters that may become intense or disruptive. The benefit offers symptomatic relief that assists with maintaining functional stability by assisting with hormonal stabilization and supporting the patient during difficult episodes of cycle irregularity.

Applied in clinical settings that involve acute or unstable symptom patterns, it provides support that helps ease the overall symptom burden.

Quick Fact: Relief for Cycle Irregularity Symptoms


Assistance for Reproductive Health Stress

In specific clinical scenarios, Clomifeno is considered relevant when supportive symptom management is appropriate for the symptoms associated with male infertility. Used in settings marked by temporary physiological imbalance, it may assist with supportive symptom management in contexts involving a heightened systemic burden. This use provides support that helps ease the overall symptom load for couples experiencing fertility challenges and contributes to easing the overall symptom load during periods of heightened symptoms.

Eligibility and Restrictions for Use

Eligibility Map: Who can and cannot use Clomifene — official regulatory information


Eligibility Scope

Populations for whom use is allowed (as stated in label): Adult women with ovulatory dysfunction (e.g., Polycystic Ovary Syndrome) who are desiring pregnancy.

Populations for whom use is contraindicated: Patients who are pregnant; those with active liver disease or history of dysfunction; individuals with abnormal uterine bleeding of undetermined origin; or those with ovarian cysts or enlargement not related to PCOS. Contraindications also include hormone-dependent tumors, uncontrolled thyroid or adrenal dysfunction, or an organic intracranial lesion like a pituitary tumor.

Age-related eligibility rules: Safety and effectiveness have not been established in pediatric patients; geriatric patient response data is insufficient.

Pregnancy and lactation eligibility status (if explicitly documented): Contraindicated in pregnancy. Caution is advised during lactation, as the medicine may suppress milk production.

Eligibility-related restrictions: Use is not recommended beyond approximately six total cycles. Caution should be exercised in patients with uterine fibroids. Efficacy for the treatment of male infertility is not established in the official label.


Eligibility Classifications (High-Level)

Eligibility severity classification (as defined in official documents): Contraindicated, Caution, Not Recommended, Not Established.

Regulatory basis (EMA / FDA / etc.): FDA Prescribing Information and EMA Summary of Product Characteristics (SmPC).

Eligibility-context constraints (as defined in official documents): Eligibility is conditional on the exclusion of pregnancy and absence of non-PCOS related ovarian enlargement before each treatment course.


Resulting Eligibility Structure

Official eligibility statements:

  • The medicine is contraindicated in patients with liver disease or who are pregnant.
  • Safety and effectiveness have not been established in the pediatric population.
  • Use is not recommended for long-term cyclic therapy.

Connection to the overall eligibility profile (2–4 sentences): Official regulatory documents define Clomifene's eligibility profile by strictly limiting its use to adult women with demonstrated ovulatory dysfunction, while mandating the exclusion of several critical health conditions and physiological states. Non-eligibility is formally declared via absolute contraindications for populations presenting with liver dysfunction, pregnancy, specific tumors, and undiagnosed uterine bleeding. Furthermore, eligibility is restricted for certain comorbidities like uterine fibroids and limited by a regulatory recommendation against extended use beyond a specified number of treatment cycles.

What should I know about interactions with other medicines?

Interactions with other medicines and products

The regulatory profile for Clomifeno (Clomiphene citrate) establishes specific interaction patterns based on official governmental documentation, focusing on pharmacodynamic risks and metabolic considerations rather than extensive drug-drug prohibitions.

Official Interaction Status and Risks

Certain regulatory authorities state that interactions between Clomifeno and other medicinal products have not been formally described.

However, a documented pharmacodynamic risk exists when Clomifeno is used in combination with other agents that stimulate ovarian function, such as Gonadotropins. This combination is officially associated with an increased risk of developing Ovarian Hyperstimulation Syndrome (OHSS), a critical consideration for combined fertility treatments.

Metabolic and Population-Specific Constraints

Clomifeno is documented to interfere with the synthesis of cholesterol, leading to elevated serum levels of desmosterol. This metabolic observation informs a specific interaction constraint for certain patient populations.

For patients with a pre-existing or familial history of hyperlipidemia or hypertriglyceridemia, the official prescribing information mandates periodic monitoring of plasma triglycerides. This requirement addresses a documented population-specific interaction risk tied to the medication's effects on lipid metabolism.

No mandatory timing-based separation rules for co-administered medicines are specified in the official regulatory documentation.

Mechanism of Action

Central Anti-Estrogenic Action and Feedback Disruption

Clomifene acts as a functional antagonist at Estrogen Receptors (ERs), primarily within the hypothalamus and the anterior pituitary gland. By competitively blocking the binding of natural estradiol, the drug disrupts the normal negative feedback loop. This action initiates a sequence where the central nervous system perceives a decrease in estrogenic feedback, which constitutes the primary molecular interaction that terminates the negative feedback inhibition on the reproductive axis.


Modulating the HPG Axis and Gonadotropin Release

The absence of estrogen receptor activation induces the central nervous system to respond via increased release of Gonadotropin-Releasing Hormone (GnRH), which in turn stimulates the pituitary to secrete elevated levels of Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH). This surge in gonadotropin concentration constitutes the key physiological change produced by the mechanism. The resulting FSH and LH concentrations stimulate follicular development and facilitate the cascade required for the eventual release of the ovum from the ovary.

Dosage and Administration Information

How to Use Clomifeno

Clomifeno (Clomiphene citrate) is an orally administered medication used in a specific, intermittent pattern. The medicine is supplied as a tablet and requires no preparation or dilution before intake.

Standard Dosing and Schedule

The dosing regimen is cyclic, meaning the medication is taken for a short, defined period followed by an off-period.

Course Type Dosage Frequency and Duration
Initial Course 50 mg Once daily for 5 days
Subsequent Course 100 mg Once daily for 5 days (only if no response to initial dose)

The daily dose should not exceed 100 mg, and the duration of any single course should not be extended beyond 5 days. Treatment is limited to a total of about six cycles.

Administration Timing

Treatment is timed within the menstrual cycle. For patients with spontaneous or progestin-induced bleeding, the first 5-day course is started on or about the 5th day of the menstrual cycle. If no recent uterine bleeding has occurred, therapy may be started at any time.

Procedural Conditions and Use Adjustments

Before initiating the first course and prior to each subsequent course, a pelvic examination is a standard procedural condition. Dosing decisions are dependent on the previous cycle's outcome; the dose is only increased from 50 mg to 100 mg if ovulation did not appear to occur. A lower initial dose or shorter duration of treatment is utilized when unusual sensitivity, such as in patients with Polycystic Ovary Syndrome (PCOS), is suspected. The next course of therapy should not be started earlier than 30 days after the previous course.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Clomifeno

Clomifeno (Clomiphene citrate) was studied for its role as a synthetic, nonsteroidal hormonal agent in the context of fertility protocols. These investigations, including Randomized Controlled Trials (RCTs) and larger reviews, aim to understand what changes researchers measured in patients during the study period.


Evidence for Use in Ovulatory Dysfunction

This section describes the body of research, including RCTs and meta-analyses, that examined Clomifeno's use in women with anovulatory infertility and related conditions like Polycystic Ovary Syndrome (PCOS). The summary describes the primary outcomes researchers measured, such as ovulation rate and clinical pregnancy rate.

Findings from trials described patterns related to the measurement of ovulation rates being higher among anovulatory patients observed during the study period. Studies also reported measurements of clinical pregnancy rates and described how these rates compared to those measured in populations receiving placebo. Research contributes to the broader evidence landscape by describing that the compound was used in studies where these short-term measurements were reported.

The follow-up durations were limited in many studies, and long-term outcomes are not fully established by the existing research. The variability of the evidence remains a focus across studies. Studies that examined Clomifeno alongside other pharmacological interventions reported mixed findings, and comparative evidence remains uncertain in some areas.


Evidence for Use in Supportive Management for Male Infertility

This part will summarize the available research, which consists primarily of smaller controlled studies and systematic reviews, focusing on the use of Clomifeno in adult males with oligospermia. It describes the hormonal and semen parameters that researchers chose to measure as endpoints in these investigations.

Some trials described patterns observed in the studies, such as increases in both hormone levels and sperm concentration measurements. A limitation noted for this use is the lack of adequate, large, or well-controlled RCTs that specifically track and are powered to measure Live Birth Rate. This means that certainty remains low for this application, and the existing research primarily provides insight into short-term changes in hormone and sperm counts, rather than definitive reproductive outcomes.

Key Studies & References

  1. Treatment of unexplained infertility with aromatase inhibitors or clomiphene citrate: a systematic review and meta-analysis
  2. Comparison of tamoxifen and clomiphene citrate for ovulation induction: a meta-analysis
  3. Clomiphene Citrate Treatment as an Alternative Therapeutic Approach for Male Hypogonadism: Mechanisms and Clinical Implications

Frequently Asked Questions (FAQ)

Common questions about Clomifeno (FAQ)


Q: Is it true that Clomifeno can thin the uterine lining?

Clomifeno is classified as a Selective Estrogen Receptor Modulator (SERM). This means it interacts with estrogen receptors in various body tissues, including the endometrium (the lining of the uterus). Official postmarketing reports have documented cases of reduced endometrial thickness associated with its use.


Q: What are the signs that Clomifeno is working for me?

The drug’s action is designed to lead to a preovulatory gonadotropin surge (a sharp rise in hormones), which is the key physiological change. Clinical testing is necessary for final confirmation. Official information does note that side effects such as pelvic pain, abdominal distension, or ovarian enlargement may occur, which reflect ovarian stimulation.


Q: What should I do if the side effects of Clomifeno are severe?

Regulatory documents state that if severe symptoms occur, particularly those associated with Ovarian Hyperstimulation Syndrome (OHSS) or visual changes, the patient should stop the medication. It is specified that the patient must contact their doctor immediately for direction.


Q: How long after taking Clomifeno should I expect ovulation to happen?

Official prescribing information indicates that ovulation usually occurs 5 to 10 days after the completion of the 5-day course of therapy.


Q: Can taking Clomifeno affect my periods once I stop taking it?

The official documentation notes that spontaneous ovulatory menstrual cycles (periods that occur naturally without medication) have been observed in some patients following Clomifeno therapy. The medicine is not intended for long-term use.


Q: How long does Clomifeno stay in your system?

Clomifeno is composed of two different forms (isomers), is readily absorbed, and is mainly excreted in the feces. The Zuclomiphene form has a long half-life. Official regulatory information indicates that detectable levels of this form may persist in the body for longer than a month.


Q: What happens if I forget to take a dose of Clomifeno?

Official patient instructions advise that if a dose is missed, the patient must contact their doctor for additional directions. It is specified that a patient should not take a double dose to compensate for the missed one.


Q: Are there any foods I should avoid while on Clomifeno?

Official patient resources state that there are typically no special dietary instructions required when taking Clomifeno. Unless a healthcare provider advises otherwise, the patient should continue their normal diet.

How should Clomifeno be stored and disposed of?

Storage and Disposal Requirements

Clomifene (clomiphene citrate) tablets must be stored and discarded according to specific regulatory guidelines to maintain potency and ensure safety.

Official Storage Conditions

Requirement Condition
Temperature Store at room temperature, typically between 59 F and 86 F (15 C and 30 C).
Protection Keep in the original container, tightly closed, and away from excess heat and moisture. Must be protected from light and not stored in the bathroom.
Child Safety Must be kept out of sight and reach of children (placed up and away).

Official Disposal Instructions

Unused or expired medication must be disposed of in accordance with local regulations. The preferred method is using a drug take-back program. If this is unavailable, mix the tablets with an undesirable substance (like coffee grounds), place the mixture in a sealed bag, and discard it in the household trash. Do not flush Clomifene down the toilet or drain.

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

Available in countries:

Equivalent of Clomifeno found in:

A-Z Index: