Usage
Centchroman is prescribed for:
- Contraception: It is primarily used as a weekly oral contraceptive pill for women of reproductive age.
- Dysfunctional Uterine Bleeding (DUB): It can be used to manage DUB, characterized by heavy or irregular menstrual bleeding.
- Other potential uses (under investigation): Research suggests potential benefits in managing mastalgia (breast pain), fibroadenoma, and certain types of cancer, but these are not yet established indications.
It’s pharmacological classification is as a selective estrogen receptor modulator (SERM).
Centchroman’s mechanism of action involves multiple effects on the reproductive system. It acts as an antiestrogen in the uterus, impeding implantation of a fertilized ovum. It hastens the transport of the ovum through the fallopian tubes, reaching the uterus before it’s ready for implantation. Additionally, it alters endometrial development, hindering its receptivity to the fertilized ovum.
Alternate Names
How It Works
Pharmacodynamics: Centchroman exerts both estrogenic and antiestrogenic effects depending on the target tissue. It primarily displays antiestrogenic activity in the uterus and breast while exhibiting estrogenic effects in bone. This unique profile contributes to its contraceptive properties without some of the typical adverse effects of hormonal contraceptives.
Pharmacokinetics:
- Absorption: Centchroman is well-absorbed orally, reaching peak serum concentrations within 3-8 hours after a single 30 mg dose.
- Distribution: It’s highly lipophilic and extensively distributed throughout the body, with a long mean residence time (around 128 days). It also binds strongly to serum albumin.
- Metabolism: Centchroman is metabolized in the liver, and 7-desmethyl centchroman is a key active metabolite.
- Elimination: Primarily eliminated through hepatic (liver) routes.
Mode of Action: Centchroman is a SERM, meaning it binds to estrogen receptors and modulates their activity. It does not inhibit ovulation. Its contraceptive effect is primarily due to its actions on the endometrium (uterine lining) and the fertilized ovum’s transport. The precise cellular and molecular mechanisms are still being investigated, but they are related to altered gene expression in the endometrium, leading to asynchronous development and preventing implantation.
Receptor binding: Binds to estrogen receptors, acting as an agonist or antagonist depending on the specific tissue.
Enzyme inhibition/Neurotransmitter Modulation: Limited data currently available on direct enzyme inhibition or neurotransmitter modulation.
Elimination pathways: Primarily hepatic excretion.
Dosage
Standard Dosage
Adults:
- Initiation: 30 mg twice a week for the first 12 weeks.
- Maintenance: 30 mg once a week thereafter, on the same day of the week as the initial dose, regardless of the menstrual cycle.
Children: Not applicable. Centchroman is contraindicated in children.
Special Cases:
- Elderly Patients: No specific dose adjustments are generally recommended, but clinical judgment is advised.
- Patients with Renal Impairment: Use with caution; dosage adjustments may be necessary.
- Patients with Hepatic Dysfunction: Use with caution; dosage adjustments may be necessary. Contraindicated in patients with active liver disease or a history of jaundice.
- Patients with Comorbid Conditions: Careful evaluation of cardiovascular risk factors is important, especially in patients with existing heart disease.
Clinical Use Cases
Centchroman is not indicated for intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations. Its use is confined to contraception and management of DUB.
Dosage Adjustments
Dosage modifications should be considered in patients with renal or hepatic impairment. Drug interactions can affect Centchroman metabolism.
Side Effects
Common Side Effects
- Menstrual irregularities (delayed periods, prolonged cycles, scanty periods)
- Nausea
- Headache
- Weight gain
Rare but Serious Side Effects
Rare and serious side effects have not been extensively documented in the literature.
Long-Term Effects
Limited information on long-term effects. Some studies have raised concerns about the potential for uterine prolapse and urinary incontinence, but these have not been definitively established.
Adverse Drug Reactions (ADR)
No specific ADRs requiring immediate intervention have been consistently reported.
Contraindications
- Pregnancy
- Breastfeeding (though considered relatively safe)
- Polycystic Ovarian Disease (PCOD)
- Cervical hyperplasia
- Active liver disease or history of jaundice
- Renal impairment
- Tuberculosis
- Severe allergic reactions
- Hypersensitivity to Centchroman
Drug Interactions
- Antibiotics: Amoxicillin might reduce contraceptive efficacy. Other antibiotics may alter Centchroman pharmacokinetics.
- Liver enzyme inducers/inhibitors: Medications affecting liver enzymes (e.g., anticonvulsants, some antibiotics) may alter Centchroman’s metabolism and effectiveness.
- Hormonal therapies: Concurrent use with hormonal contraceptives or hormone replacement therapy can have unpredictable effects on the menstrual cycle and hormone balance.
Pregnancy and Breastfeeding
- Pregnancy Safety Category: Contraindicated in pregnancy.
- Fetal Risks: Potential for adverse effects on the fetus.
- Breastfeeding: Although Centchroman does not significantly affect the quality or quantity of breast milk, caution is advised during breastfeeding, especially in the first three months postpartum.
Drug Profile Summary
- Mechanism of Action: SERM with antiestrogenic effects in the uterus and estrogenic effects in bone; alters endometrial development and ovum transport to prevent implantation.
- Side Effects: Primarily menstrual irregularities, nausea, headache, and weight gain.
- Contraindications: Pregnancy, active liver disease, PCOD, renal impairment, tuberculosis, hypersensitivity.
- Drug Interactions: Antibiotics (especially amoxicillin), liver enzyme inducers/inhibitors, hormonal therapies.
- Pregnancy & Breastfeeding: Contraindicated in pregnancy; use with caution during breastfeeding.
- Dosage: 30 mg twice weekly for 12 weeks, then 30 mg once weekly.
- Monitoring Parameters: Menstrual cycles, potential drug interactions.
Popular Combinations
No specific drug combinations are routinely recommended with Centchroman.
Precautions
- Assess for contraindications and potential drug interactions before initiating therapy.
- Monitor menstrual cycles.
- Evaluate patients for cardiovascular risk factors.
- Counsel patients on proper drug administration and potential side effects.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Centchroman?
A: 30 mg twice a week for the first 12 weeks, followed by 30 mg once a week thereafter.
Q2: How effective is Centchroman as a contraceptive?
A: It has a reported effectiveness of 98-99%, with a failure rate of 1-2 pregnancies per 100 women per year.
Q3: Can Centchroman be used during breastfeeding?
A: While generally considered safe, caution is advised, especially in the first three months postpartum.
Q4: What are the common side effects of Centchroman?
A: Menstrual irregularities (delayed or prolonged cycles, scanty bleeding), nausea, headache, and weight gain.
Q5: Does Centchroman interact with other medications?
A: Yes, it can interact with certain antibiotics (e.g., amoxicillin), medications that affect liver enzymes, and hormonal therapies.
Q6: Who should not take Centchroman?
A: Women who are pregnant, have active liver disease, PCOD, renal impairment, tuberculosis, or a hypersensitivity to Centchroman.
Q7: How does Centchroman differ from hormonal contraceptives?
A: Centchroman is non-hormonal and works primarily by altering endometrial development and ovum transport, whereas hormonal contraceptives typically inhibit ovulation.
Q8: Does Centchroman protect against sexually transmitted infections (STIs)?
A: No, Centchroman offers no protection against STIs, including HIV.
Q9: How soon can fertility return after stopping Centchroman?
A: Fertility typically returns quickly after discontinuing Centchroman due to its non-hormonal nature.
Q10: Can Centchroman be used as emergency contraception?
A: While it has been studied for emergency contraception at higher doses, it’s not its primary indication, and other dedicated emergency contraceptive methods are preferred.
