Apri 21

Quick links to important sections

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 Apri 21

Quick Facts

Property Description
Active Ingredients Desogestrel, Ethinyl Estradiol
Form Oral tablet
Pharmacological Class Combined Oral Contraceptive (COC)
Common Use Prevention of pregnancy
Origin Synthetic hormonal compounds

What Type of Medicine is Apri 21? (Definition and Classification)

Apri 21 is a prescription-only medication classified pharmacologically as a Combined Oral Contraceptive (COC). It belongs to the broader group of Estrogens/Progestins and is exclusively intended for the prevention of pregnancy in women.

The fundamental identity of this drug is rooted in its class as a hormonal preparation designed for systemic action. As a generic equivalent to certain formulations such as Ortho-Cept, it is clinically recognized for its reliability in conception control. The primary therapeutic function of this combination is contraception.

Composition and Form: Ingredients, Synthesis, and Type

Apri 21 is a combination product, formulated as a solid oral tablet, that contains two synthetic active ingredients: the progestin Desogestrel and the estrogen Ethinyl Estradiol.

The medication is a monophasic oral contraceptive, meaning that each active tablet in the blister pack provides a fixed, consistent dose of both hormonal compounds. This fixed-dose structure across the active cycle is a characteristic feature of monophasic pills. The components—Desogestrel, which is recognized as a third-generation progestogen, and Ethinyl Estradiol, a widely utilized synthetic estrogenic compound—are the agents responsible for the overall anti-conceptive effect.

Distinguishing Apri 21: A Third-Generation Combined Contraceptive

The specific progestin composition, which includes Desogestrel, is a key characteristic that places Apri 21 among combined contraceptives utilizing a third-generation progestogen. This third-generation classification provides a distinct hormonal profile compared to older combined pills that use first or second-generation progestins.

This composition leverages the combined actions of its synthetic progestin and estrogen components, delivering an established, highly effective method of conception control. The medication's core function is thus achieved through a reliable, dual-hormone strategy focused on the prevention of pregnancy.

Regulatory References

  1. Label: APRI- desogestrel and ethinyl estradiol kit - DailyMed - NIH

What side effects are possible with Apri 21?

Possible Side Effects and Safety Information

The official safety profile for Apri 21 (Desogestrel/Ethinyl Estradiol) is structured to communicate both common, expected adverse reactions and rare, serious safety risks as defined by government regulatory documents.

Frequency-Classified Adverse Reactions

The most frequently reported adverse reactions are classified as common (affecting 1% to 10% of users) and often involve the nervous and reproductive systems. These include headache, nausea, breast tenderness, and intermenstrual bleeding (spotting). Reactions classified as uncommon (affecting 0.1% to 1%) include migraine, vomiting, fluid retention, and rash. Effects such as hypersensitivity reactions and serious vascular events are classified as rare.

System-Organ-Class Groupings and Serious Risks

Adverse reactions are grouped by system-organ class. The Vascular disorders class documents the most significant safety concerns: Venous Thromboembolism (VTE), such as Deep Vein Thrombosis and Pulmonary Embolism, and Arterial Thromboembolism (ATE), including Stroke and Myocardial Infarction. Other serious documented risks include Hepatic Neoplasia and Hypertension.

Safety Constraints and Time-Related Patterns

Use is associated with an elevated thromboembolic risk compared to non-users. This risk is notably higher in certain populations, such as smokers aged over 35 years. Furthermore, official labeling states that common reactions like nausea and spotting are typically more frequent during the initial cycles of use, while the risk of certain cancers (e.g., breast, cervical) is associated with long-term exposure.

Overdose and Emergency Response

Overdose and When to Seek Help: Official Regulatory Information

Official regulatory documents classify the acute overdose of Apri 21, a combined oral contraceptive, as generally not likely to be life-threatening or associated with serious long-term adverse effects. The manifestations are typically limited to non-severe hormonal symptoms.


Documented Overdose Presentations

Acute overdose events are primarily associated with the following manifestations, as noted in official prescribing information:

  • Gastrointestinal Symptoms: Nausea and vomiting.
  • Vaginal Bleeding: This may present as either slight vaginal bleeding or withdrawal bleeding, similar to a menstrual period, occurring a few days after the overdose.

Note on Specific Populations: The presentation of slight vaginal bleeding is a documented manifestation in young girls who have ingested an overdose.


Required Emergency Actions

Despite the low risk of severe outcomes, regulatory guidance mandates immediate professional contact following any suspected overdose.

Action Required Official Regulatory Statement
Immediate Contact Seek medical help right away or contact a poison control center at once.
Antidote Status There is no specific antidote available for this medication.
Management Treatment is generally symptomatic and supportive, and may involve monitoring of vital signs.

Urgent medical attention is required to ensure appropriate assessment and supportive care, as there is no specific agent to counteract the effects of the hormones.

Therapeutic Uses of Apri 21

What Apri 21 Treats: Main Uses and Benefits

The primary therapeutic benefit of Apri 21 is realized in the domain of prophylactic reproductive control, providing effective, systematic prophylactic support for the prevention of pregnancy in women. Oral contraceptives are also commonly used to manage several other conditions where supportive symptom management is appropriate. This is relevant in clinical contexts involving temporary physiological imbalance that may create noticeable functional strain.

Management of Menstrual Cycle Disorders

The medication is commonly applied in conditions marked by chronic or episodic menstrual cycle irregularities. It is relevant for easing symptoms that interfere with daily functioning, such as heavy menstrual bleeding (hypermenorrhea) and painful periods (dysmenorrhea). This supports the patient during difficult episodes by easing distress and may help patients cope more steadily with symptom fluctuations.

Relief for Hormone-Related Skin Symptoms

Apri 21 is commonly used to help with symptoms related to systemic imbalance, including those manifesting as severe acne vulgaris and other visible signs of hyperandrogenism. This offers a supportive therapeutic approach, and the management of these symptoms may assist with maintaining functional stability and supports general well-being during symptomatic phases.


Management of Symptoms

Quick Fact: Relief Focus Relevant Symptom/Condition
Prophylactic Support Provides effective reproductive control
Cycle Stability Addresses irregular or unpredictable periods
Symptom Easing Supports relief from severe dysmenorrhea and hypermenorrhea
Dermatological Aid Helps manage severe acne vulgaris manifestations

Regulatory References

  1. NIH MedlinePlus Drug Information

Eligibility and Restrictions for Use

Official Eligibility Status for Apri 21

The use of Apri 21 (Desogestrel/Ethinyl Estradiol) is strictly defined by regulatory eligibility criteria, primarily for females of reproductive potential seeking pregnancy prevention.


Category Official Regulatory Classification
Allowed Use Females of reproductive potential.
Age-Related Rules Not indicated before menarche or in postmenopausal women. Safety and efficacy are not established in females under 18 years.
Restricted Use Lactation/Breastfeeding is not recommended. Use requires discontinuation prior to major surgery or prolonged immobilization.
Contraindicated Prohibited in females over 35 who smoke, and those with known or suspected pregnancy.

Key Contraindications

The medicine is contraindicated if a patient has a history of thromboembolic disorders, cerebral or coronary artery disease, hormone-sensitive cancers (e.g., breast, endometrial carcinoma), hepatic tumors, or severe liver disease (e.g., decompensated cirrhosis). Contraindication also applies to undiagnosed abnormal genital bleeding and concomitant use with specific Hepatitis C drug regimens.

This framework establishes absolute exclusions based on vascular, oncologic, and hepatic risk status, as mandated by official government documents.

What should I know about interactions with other medicines?

Interactions with other medicines and products

The interaction profile of Apri 21 (Desogestrel/Ethinyl Estradiol) is defined by its potential for pharmacokinetic interactions that alter the systemic exposure of its hormonal components or co-administered drugs. This information reflects restrictions and outcomes documented in official regulatory labeling.

Contraindicated Combinations

Co-administration with medicinal products containing Ombitasvir, Paritaprevir, and Ritonavir (with or without Dasabuvir) is formally contraindicated due to the officially documented risk of significant elevations in liver enzymes, specifically Alanine Aminotransferase (ALT). This restriction also applies to co-administration with products containing Glecaprevir/Pibrentasvir.

Pharmacokinetic Interactions

Substances that induce hepatic P450 enzymes, such as the anticonvulsants Phenytoin and Carbamazepine, the anti-infective Rifampicin, and the herbal product St. John’s Wort, are documented to decrease the plasma concentrations of the contraceptive hormones. This interaction results in reduced contraceptive effectiveness. Conversely, the co-administration of CYP inhibitors may cause an officially observed increase in the exposure to the hormonal components. Furthermore, the drug may increase the plasma concentration of certain co-administered drugs, including beta-blockers. Etoricoxib is also documented to increase the exposure to combined hormonal contraceptives.

Administration-Timing Interaction

Official labeling specifies that events leading to incomplete absorption, such as vomiting or severe diarrhea occurring within 3 to 4 hours of administration, are equivalent to a missed dose and can reduce contraceptive effectiveness.

Mechanism of Action

How Apri 21 Works

Central Regulation of the HPO Axis

The core mechanism involves Ethinyl Estradiol and the active progestin Etonogestrel acting as agonists at the Estrogen and Progesterone Receptors (ER/PR), respectively. This activates a pronounced negative feedback inhibition loop on the Hypothalamic-Pituitary-Ovarian (HPO) axis . This feedback suppresses the pituitary's release of Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH), resulting in the primary physiological effect of suppression of ovulatory signals.

Peripheral Reproductive System Barriers

The drug employs two complementary peripheral mechanisms via local tissue modulation. The progestin component modifies the cellular activity of the cervical glands, causing the mucus to become notably thickened and viscous—a physical barrier that impedes sperm transport. Concurrently, the combination of hormones alters the structure of the endometrium (uterine lining), rendering the tissue altered for implantation.

Mechanistic Complementation and Limitations

The combination exhibits pharmacodynamic complementation, with the progestin providing the main LH suppression and the estrogen augmenting FSH suppression and supporting consistent hormonal patterning within the uterine lining. The mechanism, however, can be functionally weakened by the co-administration of CYP enzyme-inducing drugs, which accelerate the breakdown of the hormones, potentially compromising the required concentration for consistent pathway suppression.

Dosage and Administration Information

How to Use Apri 21: Official Administration Guidelines

The usage of Apri 21 is governed by a fixed-dose, 28-day cyclic pattern, where one tablet is administered daily. This schedule defines both the precise timing and the sequence of tablet intake.

Administration Structure

Category Official Administration Rule
Route of Administration The medication is taken orally in tablet form.
Dosing Schedule One tablet containing 0.15 mg Desogestrel and 0.03 mg Ethinyl Estradiol is taken daily for 21 days, followed by 7 days of an inactive (placebo) tablet.
Timing & Consistency The tablet must be taken at the same time each day to maintain the consistent hormonal input.
Age-Group Rules The medication is not indicated for use before menarche or in postmenopausal women. Safety and effectiveness are not established in women under 18 years of age.

Resulting Procedural Structure

The official regimen provides two initiation methods for the first cycle: the Day 1 Start (first day of menstrual bleeding) or the Sunday Start (first Sunday after the period begins). If the Sunday Start is used, instructions require an additional non-hormonal method for the first seven days of the first cycle.

Tablets must be taken in the order directed on the blister pack, ensuring the sequence of active tablets is completed before starting the inactive tablets. Upon finishing the 28-day course, a new pack is started immediately, with no break between cycles. Specific procedural instructions exist for handling missed active tablets, which vary based on the number of tablets missed and the week of the cycle.

This administration protocol is structured around consistent, daily adherence to the fixed-dose cyclic course.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Apri 21

Evidence for Use in Preventing Pregnancy (Contraception)

The primary body of research for Apri 21, which contains desogestrel and ethinyl estradiol, was evaluated in research exploring patterns related to pregnancy incidence. This area is characterized by research that includes primary supporting clinical trials and extensive observational cohort studies. Researchers specifically examined the rate of unintended pregnancy, tracked using the Pearl Index across studies involving women of reproductive potential.

In regulatory submissions, the findings from clinical trials conducted under ideal conditions—adhering strictly to protocol—reported specific measurements of pregnancy incidence consistent with the drug class. Observational studies applied in real-world settings described patterns where the incidence of unintended pregnancy was different when accounting for inconsistencies and errors typical of daily use. The overall body of evidence describing these patterns is noted in regulatory documents for the combined oral contraceptive class as a whole.

Research on Using Apri 21 for Menstrual Cycle Symptoms and Acne Management

Research has also explored outcomes related to conditions characterized by fluctuating symptoms, specifically painful periods (dysmenorrhea), menstrual blood loss, and mild to moderate acne vulgaris. This research often uses randomized controlled trials (RCTs) and systematic reviews.

For painful periods, studies monitored changes in reported pain intensity and tracked the use of supplementary pain medication. Research describes patterns where a change in mean pain scores was seen in the groups using combined hormonal preparations. Similarly, trials evaluating acne reported measurements of changes in the number of acne lesions and patterns observed in global assessment scores.

Research Gaps and Areas of Uncertainty

While short-term results are documented, long-term study findings often rely on extrapolation from general studies of combined oral contraceptives (COCs) rather than specific, multi-decade trials for every single formulation. Data for certain groups remain insufficient; most controlled trials focus on generally healthy women of reproductive age, meaning limited information exists for populations with complex underlying health conditions (comorbidities).

Key Studies & References An Efficacy and Safety Study Comparing Oral Contraceptive Containing Norgestimate or Desogestrel for Acne Treatment (ClinicalTrials.gov ID NCT01466673)

Frequently Asked Questions (FAQ)

Common questions about Apri 21 (FAQ)


Q: Is Apri 21 only for its main approved use?

A: The official labeling for Apri 21 indicates the medication is primarily used for the prevention of pregnancy. Regulatory documents and clinical studies have also explored outcomes related to other health conditions. However, for any uses beyond conception control, official labeling should be consulted with a healthcare professional for the most accurate information.


Q: What is the difference between Apri 21 and other similar combination drugs?

A: Apri 21 is classified as a monophasic combined oral contraceptive. This means every active pill contains the same fixed dose of hormones throughout the cycle. Its distinguishing characteristic is the use of Desogestrel, which is categorized by official sources as a third-generation progestin.


Q: Is weight gain a common side effect described for Apri 21?

A: Official product information does not commonly list weight gain in its frequency-classified adverse reactions list. However, a potential effect described in the precautions section is fluid retention. This temporary increase in body fluid is recognized as a possible effect of combined hormonal preparations.


Q: Can Apri 21 cause changes to mood or anxiety?

A: Regulatory labeling includes a precaution regarding emotional disorders in women using this medication. Official documents advise that individuals with a history of depression should be observed carefully while taking the drug. The issue should be addressed if depression recurs or becomes severe.


Q: Do side effects from Apri 21 usually go away after a few months?

A: According to the official product information, common initial effects like nausea and intermenstrual bleeding (spotting) are typically observed more frequently during the first few cycles. This indicates a pattern where the frequency of these reactions may change as the body adjusts to the medication.


Q: Can antibiotics like amoxicillin change how Apri 21 works?

A: Official labeling indicates that certain broad-spectrum antibiotics, including Amoxicillin, may affect the intestinal flora. These medications can potentially interfere with the reabsorption of the estrogen component, which may lead to reduced contraceptive efficacy.


Q: Is it necessary to separate the timing of Apri 21 from taking acetaminophen?

A: Official documents describe an interaction where the estrogen component of Apri 21, Ethinyl Estradiol, may have its circulating levels increased when taken with acetaminophen. This occurs because of the way the body processes the medications, which can lead to higher circulating hormone levels.


Q: Do grapefruit products affect the way the body handles Apri 21?

A: Regulatory sources list grapefruit juice as a substance that can interact with the hormones in Apri 21. Grapefruit juice is a known CYP3A4 inhibitor, which is a process that may increase the plasma concentrations of the hormonal components in the bloodstream.


Q: Are there interactions listed for Apri 21 and common antifungal medicines?

A: Yes, the official interaction profile includes certain antifungal medications such as fluconazole and itraconazole. These are listed as CYP3A4 inhibitors, which may lead to increased plasma concentrations of the contraceptive hormones.


Q: Is it true that the effects of Apri 21 build up over multiple cycles?

A: Clinical pharmacology data indicates that the hormones in Apri 21 take time to reach a consistent level in the body. The active metabolite, 3-keto-desogestrel, is observed to reach steady state (consistent concentration) from at least Day 19 onwards in the third cycle of use.


Q: How long does Apri 21 stay in the body after the last dose?

A: The speed at which the hormones are eliminated from the body is measured by the half-life. At steady state, the elimination half-life for the active metabolite (3-keto-desogestrel) is approximately 38 hours, and for ethinyl estradiol is approximately 26 hours.


Q: Can Apri 21 be used by people with a history of certain types of migraines?

A: Official regulatory documents list a history of certain migraine types as a contraindication for using Apri 21. Specifically, the medication is prohibited for individuals who experience headaches with focal neurological symptoms, such as aura.


Q: What is the difference between the 21-day pack and the 28-day pack of this medication?

A: The standard administration guideline involves a 28-day regimen, which consists of 21 days of active tablets followed by 7 days of inactive (placebo) tablets. The standard 28-day pack includes these 7 inactive pills, whereas a 21-day pack would contain only the active pills.


Q: Can Apri 21 affect laboratory blood test results?

A: Yes, the regulatory labeling for Apri 21 includes information regarding potential interactions with laboratory tests. The hormonal components of the medication may affect the results of certain blood tests, and this potential effect is documented in official sources.


Q: Does Apri 21 contain any ingredients derived from animals?

A: Official product labeling contains a full description of all ingredients, including both active components and inactive excipients. This comprehensive list is the source for determining the specific components of the medication, including whether it contains any animal-derived ingredients.


Q: Is Apri 21 described as being lactose-free or containing common allergens?

A: The official labeling for this product includes a complete list of inactive ingredients (excipients), which is available in the Description section of the regulatory documents. This list contains the necessary information to determine the presence of common allergens, such as lactose.


Q: Do regulators require specific monitoring tests while taking Apri 21?

A: Regulatory documents advise that during the follow-up physical examination, special attention should be paid to blood pressure, breasts, and pelvic organs. Furthermore, the official labeling recommends that relevant laboratory tests be performed as part of this follow-up.


Q: Is there guidance on taking Apri 21 if a person is overweight?

A: Official warnings and precautions state that the risk of serious side effects is elevated in the presence of underlying risk factors. Obesity is specifically listed in regulatory documents as one of these underlying factors.


Q: Are there any food restrictions mentioned for Apri 21 beyond grapefruit?

A: The official administration guidelines address events that lead to incomplete absorption after the tablet is taken orally. The labeling states that instances of vomiting or severe diarrhea occurring within 3 to 4 hours of administration are considered equivalent to a missed dose.


Q: Has Apri 21 been studied in different ethnic populations?

A: The clinical pharmacology and clinical studies sections of the official labeling contain information on specific populations and subgroups included in the research. This is the source for data that addresses potential differences in how the medication is processed by various ethnic populations.


Q: Is Apri 21 a scheduled drug by any regulatory body?

A: Apri 21 is officially classified as a prescription-only medication. The regulatory labeling does not include an official DEA Schedule classification, which indicates it is not designated as a controlled substance.


Q: What are the official contraindications for taking Apri 21 with a history of migraines?

A: Official regulatory documents list a history of certain migraine types as a contraindication for using Apri 21. Specifically, the medication is prohibited for individuals who experience headaches with focal neurological symptoms, such as aura.

How should Apri 21 be stored and disposed of?

Storage & Disposal Scope

Labeled storage temperature requirements: Store at a controlled room temperature, specifically between 15 C and 30 C (59 F and 86 F).
Light/moisture protection requirements: The medication must be kept away from excessive heat, moisture, and direct sunlight.
Packaging-related storage rules (if applicable): Keep the tablets in the original container/blister card and keep the packaging tightly closed.
Disposal instructions (as documented in government sources): Dispose of unused or expired product safely, in accordance with local regulations. Return to a pharmacy for proper disposal (take-back program is often advised).
Child-protection storage requirements (if stated): The product must be kept out of the reach and sight of children and pets in a secure location.

Official storage and disposal statements:

Official regulatory documents require Apri 21 to be stored at a stable, controlled room temperature, within the range of 15 C to 30 C. The tablets must be protected from excessive heat and moisture to maintain product stability and integrity up to the labeled expiry date. The medication must remain in its original container and be kept out of the reach of children. Unused or expired tablets should be disposed of safely, following local regulations, often by utilizing pharmaceutical take-back programs.

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

Available in countries:

Equivalent of Apri 21 found in:

A-Z Index: