Slynd
Slynd
Generic Name
Slynd
Mechanism
- Dual inhibition of ovulation:
- Desogestrel suppresses the hypothalamic‑pituitary‑gonadal (HPG) axis, preventing the mid‑cycle LH surge.
- Ethinyl estradiol provides negative feedback, further blunting LH/FSH release.
- Alteration of cervical mucus: Progestin thickens mucus, reducing sperm penetration.
- Endometrial suppression: Low estrogen/progestin ratio slows endometrial proliferation, reducing menstrual bleeding.
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Pharmacokinetics
| Parameter | Value | Comments |
| Absorption | Rapid; peak plasma levels within 1–2 h (desogestrel) | Food may delay absorption slightly |
| Bioavailability | 90–100 % | No first‑pass effect |
| Metabolism | CYP3A4‑dependent | Agents that induce or inhibit CYP3A4 alter serum levels |
| Half‑life | Desogestrel 8–10 h; ethinyl estradiol 13–21 h | Allows daily dosing with 24‑hour coverage |
| Excretion | Urinary (50 %) and fecal (45 %) | Minimal renal impairment effect |
| Population variability | No significant adjustment required for age, weight, or ethnicity |
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Indications
- Permanent or reversible contraception in healthy women aged 12–49 years.
- Management of menorrhagia—reduces menstrual blood loss by 30–50 %.
- Control of oligomenorrhea—regularizes cycle length.
- May be used as a backup for emergency contraception (within 5 days of unprotected intercourse) when combined with a Plan B‑like regimen.
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Dosing
- Standard regimen: Take one tablet daily at the same time for 24 consecutive days, followed by a 4‑day pill‑free interval.
- Rescue: If a dose is missed (≤24 h), take immediately; if >24 h, take the most recent pill and swallow the most recent missed dose.
- Desire for shortened cycle: Some prescribers may offer a 24/4‑day schedule vs. 28/4; discuss with provider.
- Special populations:
- Post‑menarche <18 y: Initiate at amenorrhea onset.
- Obese: No dose adjustment needed; monitor for reduced efficacy.
- Storage: Store at ambient temperature (18–30 °C). Do not store in a refrigerator.
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Monitoring
- Baseline: BP, weight, medical history (VTE risk, smoking status).
- Follow‑up:
- Periodic BP checks (#1–3 months).
- Weight trend > 5 % may prompt reevaluation.
- Monitor for unexplained bleeding or pain.
- Lab monitoring: Not routine; consider LFTs if hepatic disease suspected or symptoms emerge.
- Pregnancy test: If amenorrhea/oligomenorrhea persists beyond 2 months.
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Clinical Pearls
- “First‑dose timing”: Start at first day of menses to minimize breakthrough bleeding.
- Track missed pills: A log helps identify patterns and maintain efficacy.
- Interactions via CYP3A4: Use non‑prescription supplements (e.g., St. John’s Wort) cautiously; they can lower efficacy.
- Weight‑stable patients: Daily dosing remains effective; avoid dose changes solely for weight fluctuations.
- Emergency contraception synergy: If using Slynd as a backup, add a levonorgestrel‑based Plan B‑like regimen 5 days post‑intercourse.
- VTE risk stratification: A simple “STOP” rule (Smoker, Thrombophilia, Obesity, Pregnancy) helps decide candidacy.
- Menstrual suppression: Three consecutive 24‑day cycles can significantly reduce heavy bleeding, but counsel about potential hormonal side‑effects.
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• References
1. *American College of Obstetricians and Gynecologists. Updated Practice Bulletin No. 165—Recent Guidelines for Oral Contraceptives.*
2. *Food and Drug Administration. Slynd (Desogestrel/ethinyl estradiol) prescribing information.*
3. *World Health Organization. WHO Medical Eligibility Criteria for Contraceptive Use. 2023 edition.*
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