Lomifen

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Medically reviewed

Marina Burgos

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 Lomifen

Lomifen is a prescription pharmaceutical preparation primarily known as a fertility treatment drug used to manage specific causes of female infertility related to problems with the reproductive cycle. Its fundamental role is to act as an ovulation stimulator, utilizing a precise synthetic compound to encourage the necessary hormonal signals for egg release. The drug's mechanism focuses on anovulatory or oligo-ovulatory infertility.

Property Description
Active ingredient Clomifene Citrate (Clomifene)
Form Oral Tablet
Pharmacological class Selective Estrogen Receptor Modulator (SERM)
Common use Ovulation induction
Origin Synthetic Compound (Nonsteroidal)

What Type of Medicine is Lomifen and its Composition?

Lomifen's active ingredient is Clomifene Citrate (Clomifene), which is classified as a Selective Estrogen Receptor Modulator (SERM). This means it is a synthetic compound, a nonsteroidal estrogen derivative, and is administered as a single-ingredient oral tablet. The use of Clomifene as an initial intervention is widely clinically recognized for decades in reproductive medicine. As a SERM, it functions by interacting selectively with estrogen-sensing tissues in the body, primarily influencing the brain's hormone regulation centers.

How Does Lomifen Function to Assist Fertility?

The primary purpose of Lomifen is to address difficulties with ovulatory dysfunction or anovulation by indirectly influencing the body's hormone production. The drug temporarily occupies estrogen receptors in the hypothalamus, causing the regulatory center to perceive a hormonal deficit. This perceived shortage triggers a reflexive release of key hormones, gonadotropins—Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH)—hormones crucial for initiating the growth and maturation of an ovarian follicle. In a typical use scenario, this oral medication is administered during the early phase of the menstrual cycle to prompt the brain and ovaries to synchronize hormone production, leading toward successful egg release.

Why is Lomifen Considered a Foundational Fertility Agent?

Lomifen is often considered a foundational or initial therapeutic option because it employs a synthetic compound to stimulate the body's own natural hormonal pathways, which is generally a less invasive intervention than direct hormone injections. Administered conveniently as an oral medication (tablet), this approach allows female patients struggling with irregular cycles to receive a targeted fertility treatment designed to promote a functional and regular cycle. This positioning contrasts with other fertility agents that require a strictly monitored injection route, making Clomifene a distinct, manageable option in the continuum of reproductive care.

What side effects are possible with Lomifen?

Possible side effects and safety information

The official safety documentation for Lomifen (Clomiphene Citrate) classifies possible adverse reactions by frequency and affected body system, providing a framework for understanding its risk profile.

Adverse Reaction Scope

Classification Examples of Reactions Affected Systems (SOC)
Very Common Vasomotor flushing (hot flashes) Vascular Disorders
Common Ovarian enlargement, abdominal discomfort, nausea, vomiting, headache, breast discomfort, visual blurring, scotomas (spots/flashes) Reproductive System, Gastrointestinal, Nervous System, Eye Disorders
Uncommon Depression, insomnia, dizziness, fatigue, urticaria (hives), uterine hemorrhage Psychiatric Disorders, Skin and Subcutaneous Tissue

Serious Adverse Reactions and Safety Constraints

The regulatory safety profile explicitly documents a risk of Ovarian Hyperstimulation Syndrome (OHSS), a potentially serious condition that can involve rapid progression. Additionally, the label notes an increased incidence of multiple births and a potential association with ectopic pregnancy.

Time-related patterns are noted, particularly for visual symptoms, which are generally reported to be reversible upon immediate discontinuation, although cases of prolonged or persistent disturbance have been documented.

Use of Lomifen is contraindicated in women who are pregnant or have a history of liver disease or impaired hepatic function. The medicine is also restricted in patients with undiagnosed abnormal uterine bleeding or specific ovarian enlargement or cysts (other than those due to Polycystic Ovary Syndrome).

This structured information is derived from government regulatory documents, formally outlining the boundaries of the medicine's safety profile.

Overdose and Emergency Response

The official regulatory profile for Lomifen (Clomiphene Citrate) overdose is defined by specific physical and clinical manifestations documented in government labeling.

Overdosage is associated with documented gastrointestinal symptoms, including nausea, vomiting, abdominal pain, and stomach swelling. Critical manifestations noted in official prescribing information include visual disturbances such as blurred vision, scotomata (blind spots), and scintillating scotomata (flashes). The physical sign of ovarian enlargement is also documented in overdosage situations.

A significant risk associated with excessive exposure is the potential for potentially irreversible visual disturbances and the precipitation of severe Ovarian Hyperstimulation Syndrome (OHSS), a life-threatening complication.

In all suspected cases of overdose, official guidance mandates that an individual seek immediate medical attention or call a Poison Control Helpline. If the person has collapsed, is seizing, or has difficulty breathing, emergency services must be called immediately.

Management is symptomatic and supportive, as regulatory documents state that no known specific antidote is available. Furthermore, if any visual symptoms are noted, the medication must be permanently discontinued, and a complete ophthalmological evaluation is required.

Therapeutic Uses of Lomifen

Lomifen is commonly used for managing specific types of female infertility to help with the lack of spontaneous egg release. The medication is applied in situations where patients experience symptoms related to systemic imbalance, which may include the difficulty of achieving natural egg release.

The medication is relevant for addressing ovulatory dysfunction and is generally considered for conditions characterized by an underlying hormonal imbalance, such as anovulatory infertility, oligo-ovulatory infertility, and the ovulatory component of Polycystic Ovary Syndrome (PCOS). It addresses the symptomatic pattern of irregular or absent menstrual cycles in women seeking to conceive.

Lomifen is generally employed as a supportive management strategy, offering an initial, manageable approach to assist with conception efforts. This application supports the clinical goal of improving the reproductive cycle's functionality. By targeting the processes that assist with stimulating follicle growth, the therapeutic benefit supports general well-being during symptomatic phases of subfertility by assisting with maintaining functional stability.

Quick Fact: Relief for Ovulatory Dysfunction This medication is commonly used to help with the symptomatic manifestation of infrequent and unpredictable egg release.

Regulatory References

  1. NIH MedlinePlus overview of Clomiphene

Eligibility and Restrictions for Use

Lomifen (Clomifene Citrate) is strictly authorized for use in adult women of reproductive age who have been diagnosed with ovulatory dysfunction and desire pregnancy. The eligibility profile is defined by stringent exclusions and limitations documented in official regulatory labeling.

Contraindicated Populations Key Eligibility Restrictions
Pregnant women Use is limited to approximately six total treatment cycles (ovulatory cycles).
History of liver disease or liver dysfunction Caution is advised for patients with uterine fibroids or endometriosis.
Undiagnosed abnormal uterine bleeding Not established or indicated for use in pediatric or geriatric populations.
Ovarian cysts or enlargement not due to PCOS Caution is necessary in breastfeeding women due to potential to reduce lactation.
Organic intracranial lesions (e.g., pituitary tumor) Contraindicated in uncontrolled thyroid/adrenal dysfunction.

Eligibility is conditional upon the exclusion of pregnancy and hepatic impairment, which are absolute regulatory exclusions. The label mandates that non-PCOS-related ovarian enlargement and uncorrected endocrine disorders must be ruled out prior to administration.

What should I know about interactions with other medicines?

Interactions with other medicines and products

The official regulatory profile for Lomifen (Clomifene Citrate) is primarily defined by the explicit finding that drug interactions with other medicines have not been documented. This determination, made by major regulatory bodies such as the U.S. FDA and European agencies, indicates that specific pharmacokinetic (e.g., enzyme-mediated changes in exposure) and pharmacodynamic interactions with co-administered substances are none known.

A key restriction relates to the administration of specific hormonal agents. If treatment with progestins is prescribed during a cycle initiated by Clomifene Citrate, regulatory documents stipulate a mandatory timing requirement. These substances must not be given before day 20 of the cycle to prevent interference with the therapeutic objective.


Interaction-Context Constraints

The product's clearance pathway establishes a critical constraint related to a patient's physiological state. Clomifene Citrate therapy is formally contraindicated in individuals with pre-existing liver disease or a history of liver dysfunction. This restriction is necessary because the drug's metabolism and subsequent clearance via enterohepatic circulation can be affected by impaired hepatic function. No interactions with food, alcohol, or herbal products are officially documented in the prescribing information.

Mechanism of Action

Modulating the Central Hormone Feedback Loop

Lomifen, a Selective Estrogen Receptor Modulator (SERM), initiates its action by binding to estrogen receptors in the hypothalamus and pituitary gland, functioning as a competitive antagonist. By occupying these central receptors, the drug blocks the normal negative feedback signal transmission exerted by endogenous estrogen . This signal modification disinhibits the hypothalamus, resulting in an increased pulsatile release of Gonadotropin-Releasing Hormone (GnRH), which dictates the cascade.

Upregulating Gonadotropin Signaling

This central interference is followed by a surge in the secretion of Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH) from the pituitary gland. This marked pharmacological upregulation of gonadotropin signaling alters the setpoint of existing hormonal regulation, providing the stimulus for peripheral processes.

Inducing Follicular Maturation

High circulating LH and FSH levels act on the ovaries to stimulate follicular growth and maturation. Subsequently, the LH surge induces luteinization—the formation of the corpus luteum—which results in an increase in progesterone concentration, contributing to the full sequence of reproductive endocrine changes.

Dosage and Administration Information

Lomifen (Clomifene Citrate) is administered exclusively as an oral 50 mg tablet for use in cyclical regimens. The instructions define a highly structured pattern governed by the patient’s menstrual cycle and a fixed dose escalation schedule.


Administration Guidelines

Instruction Detail
Route and Strength Administered by mouth as a 50 mg tablet.
Initial Dosing Schedule The first course is 50 mg once daily for five consecutive days. Therapy typically begins on or about the fifth day of the menstrual cycle.
Dose Progression If ovulation does not occur after the initial course, the dose for the subsequent course is increased to 100 mg once daily for five days. The dose should not be increased if ovulation occurs at the 50 mg level.
Cycle Timing and Limits The dose or duration should not be increased beyond 100 mg daily for 5 days. Long-term cyclic therapy is generally not advised beyond a total of about six cycles.

Procedural Prerequisites

Instructions mandate specific conditions be met before starting each course. Treatment is restricted to patients with normal liver function. A pelvic examination is mandatory prior to the first course and must be repeated before each subsequent course to screen for ovarian enlargement or pregnancy. For patients with Polycystic Ovary Syndrome, a lower dosage or shorter duration of treatment is specifically recommended due to potential sensitivity.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Lomifen


Evidence for Anovulatory and Oligo-ovulatory Infertility

Research on Lomifen has explored outcomes through Randomized Controlled Trials (RCTs) and systematic reviews. These studies were applied in research contexts involving adult women whose conditions were characterized by functional limitations related to the menstrual cycle, specifically the failure to spontaneously release an egg. Researchers monitored the frequency of confirmed ovulation over defined time intervals to determine what patterns were observed in the populations.

Research highlights changes measured during the study period, with findings describing that ovulation was frequently observed in the populations studied. However, studies report how symptoms evolved in the observed populations, and research so far indicates that the rate of achieving a clinical pregnancy and a live birth was lower than the measured ovulation rate in the same study groups.


Comparing Lomifen to Other Therapeutic Approaches

Research has evaluated Lomifen in comparative settings, including those that examined it against a placebo or against observation alone (expectant management). Studies were also conducted comparing Lomifen to other pharmacologic agents for ovulatory dysfunction, such as metformin and letrozole. In settings where Lomifen was compared to a placebo, findings describe patterns related to measured ovulation occurrences.

Studies comparing Lomifen to metformin in specific groups, such as some patients with Polycystic Ovary Syndrome (PCOS), explored how outcomes varied depending on patient characteristics, and comparative findings were mixed across all possible subgroups.


Key Research Gaps and Uncertainties

A consistent research limitation describes patterns where high rates of measured ovulation were not associated with similarly high live birth rates. Studies suggest this was observed alongside research exploring factors like the endometrial lining, but certainty remains low. The available evidence is limited and heterogeneous for the use of Lomifen in studies involving couples with unexplained infertility, making it difficult to draw consistent conclusions for this particular indication. Long-term effects are not fully established, as follow-up durations were often limited.

Key Studies & References

  1. Clomiphene (Clomifene Citrate) - MedlinePlus Drug Information

Frequently Asked Questions (FAQ)

Common questions about Lomifen (FAQ)

Q: How quickly does Lomifen usually start working?

A: Lomifen begins the process of ovulation induction indirectly by influencing the central hormone centers in the brain. According to official information regarding typical usage, ovulation is most often expected to occur 5 to 10 days after the final dose of the five-day course of therapy is completed. This time frame is when the medication’s intended effect on ovulation is most frequently observed.

Q: Do I need to take Lomifen at a specific time of day?

A: The official prescribing information for Lomifen defines the daily dose and the overall start date within the menstrual cycle, but it does not specify a mandatory time of day for taking the tablet. However, clinical practice guidelines often note that taking the medication at the same time each day throughout the five-day course may support routine consistency.

Q: What happens if I forget to take a scheduled amount of Lomifen?

A: Official regulatory documents do not provide a specific protocol or instruction for patients who miss a dose. Some clinical guidelines generally describe that a missed dose may be taken as soon as it is remembered, provided it is not time for the next scheduled dose. Official guidelines caution against taking two doses at once.

Q: Can Lomifen cause changes in mood or sleep?

A: Yes, official reports include that Lomifen may be associated with changes in the nervous and psychiatric systems. Reported side effects include insomnia (difficulty sleeping) and depression. Postmarketing reports also list other related effects such as anxiety, irritability, and mood changes.

Q: What should I know about taking Lomifen with alcohol?

A: The official regulatory profile for Lomifen states that a specific interaction with alcohol has not been documented in the prescribing information. However, safety sources describe that consuming alcohol may potentially be associated with an increased occurrence of certain side effects.

Q: Are there any long-term effects associated with using Lomifen?

A: Official regulatory documents state that long-term cyclic therapy is generally restricted to a total of about six cycles. The regulatory information notes that infertility itself is a risk factor for ovarian cancer, and some epidemiological studies suggest that prolonged use of this medication may be associated with an increased risk of a borderline or invasive ovarian tumor.

Q: Is Lomifen the same kind of drug as other common treatments for the condition it treats?

A: Lomifen is classified as a Selective Estrogen Receptor Modulator (SERM), meaning it works by influencing estrogen receptors to indirectly prompt the release of hormones. This pharmacological class is distinct from other fertility treatments, such as direct injectable gonadotropin hormones, by using the body's own system to stimulate ovulation.

Q: Are there any common over-the-counter pain relievers that interact with Lomifen?

A: The official regulatory profile for Lomifen specifies that drug interactions with other medicines have not been documented in the prescribing information. This general statement applies to common over-the-counter pain relievers.

Q: Is it normal to feel tired or dizzy when first starting Lomifen?

A: Official documents list dizziness and fatigue as reported side effects. While regulatory information describes these as general adverse events, it does not specify whether they are more common during the initial days of treatment. The experience of any symptoms should be discussed with a healthcare professional for individual guidance.

Q: Can Lomifen affect my ability to drive or operate machinery?

A: Yes, official warnings advise caution regarding activities that require alertness. Due to the reported possibility of visual symptoms (such as blurring or scotomas) or general dizziness, patients are advised that their ability to drive or operate heavy machinery may be impaired while using the medication.

Q: What is the connection between Lomifen and weight change?

A: The official documentation includes reports of both weight gain and weight loss as postmarketing adverse events associated with the use of Lomifen.

Q: Are there specific food types I should avoid while using Lomifen?

A: According to the official prescribing information, no interactions with food are documented. This indicates that there are no specific food types that must be strictly avoided while taking the medication.

Q: Is there a generic version of Lomifen available?

A: Yes, the active ingredient in Lomifen, Clomifene Citrate, is available as an FDA-approved generic formulation.

Q: Does Lomifen interact with common supplements like vitamins or herbal remedies?

A: The official regulatory profile states that drug interactions with other medicines and products, including herbal products, have not been documented. This general statement applies to common vitamins and herbal remedies.

Q: Can older adults typically use Lomifen safely?

A: Lomifen is indicated for use exclusively in adult women of reproductive age. The drug's safety and effectiveness have not been established for use in the geriatric population (older adults).

Q: What should I do if the side effects of Lomifen seem severe?

A: The official product information describes potentially severe adverse reactions like Ovarian Hyperstimulation Syndrome (OHSS) and persistent visual symptoms. These conditions are described in official documents as potentially serious and typically necessitate immediate discontinuation of the medication and prompt medical assessment.

Q: Does Lomifen cause changes in blood pressure?

A: The official postmarketing adverse events list includes reports of hypertension, which is the medical term for high blood pressure.

Q: Can I take Lomifen if I am already on treatment for a different long-term health issue?

A: Lomifen is contraindicated in patients with certain pre-existing conditions. These include uncontrolled endocrine disorders such as uncontrolled thyroid or adrenal dysfunction, or if the patient has an organic intracranial lesion (for example, a pituitary tumor).

Q: What happens to Lomifen in the body after I take it?

A: The drug is extensively metabolized by the liver and is eliminated slowly. Official pharmacokinetic data indicates it undergoes enterohepatic circulation, meaning it is reabsorbed from the intestine. This process contributes to the drug having a prolonged presence in the body after administration is complete.

How should Lomifen be stored and disposed of?

How to Store and Dispose of Lomifen?

Lomifen (Clomiphene Citrate) tablets must be stored according to official regulatory requirements to ensure stability and integrity.


Storage Conditions

Requirement Official Instruction
Temperature Store at Controlled Room Temperature, typically 15 to 30 C (59 to 86 F).
Handling Keep from freezing and away from excess heat.
Protection Protect from light and excessive humidity.
Packaging Store in the original, closed container.
Safety Keep out of the sight and reach of children.

Disposal Instructions

Unused or expired Lomifen must be handled safely. Official labeling requires that the disposal of the contents and container be done in accordance with local and national regulations for pharmaceutical waste. The product is not classified as hazardous waste requiring special protocols beyond standard local regulations, but outdated medicine should not be kept or improperly discarded.

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

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