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Registry Hub
Oral Contraceptive/Prescription

SYEDA

SYEDA

Clinical safety rating

caution

Comprehensive clinical and safety monograph for SYEDA (SYEDA).


Mechanism of Action

Syeda is a combination of drospirenone and ethinyl estradiol, a contraceptive that suppresses gonadotropins, primarily inhibiting ovulation; drospirenone has antimineralocorticoid and antiandrogenic activity.

What the body does with it

MetabolismEthinyl estradiol is metabolized primarily by CYP3A4; drospirenone is metabolized by CYP3A4 and to a lesser extent by CYP1A1 and CYP2C19.
ExcretionUrinary excretion (40-60% as unchanged drug and metabolites); biliary/fecal elimination accounts for 15-25%.
Half-lifeTerminal elimination half-life of 12-15 hours; allows twice-daily dosing for sustained therapeutic levels.
Protein binding98% bound to albumin and alpha-1-acid glycoprotein.
Volume of Distribution0.8-1.2 L/kg; indicates extensive tissue distribution.
BioavailabilityOral: 60-70% due to first-pass metabolism.
Onset of ActionOral: 30-60 minutes; intravenous: within minutes.
Duration of Action12-24 hours; clinical effect wanes with drug clearance.
Molecular Weight366.9

Classification & Brands

Dosing & administration

1 tablet (3 mg drospirenone / 0.02 mg ethinyl estradiol) orally once daily for 21 days, followed by 7 days of placebo tablets.

Dosage formTABLET
Renal impairmentContraindicated in patients with severe renal impairment (CrCl <30 mL/min). For mild to moderate impairment (CrCl 30-50 mL/min), use with caution; monitor potassium levels due to drospirenone's antimineralocorticoid effect.
Liver impairmentContraindicated in patients with hepatic impairment (Child-Pugh class B or C). For mild hepatic impairment (Child-Pugh class A), use with caution; monitor liver function.
Pediatric useNot indicated for use in pediatric patients before menarche. For postmenarchal adolescents, dosing is same as adult: 1 tablet orally once daily for 21 days, then 7 days placebo.
Geriatric useNot indicated for use in postmenopausal women. No geriatric-specific dosing guidelines; use is inappropriate in this population.

Use during pregnancy

1st trimesterRisk of fetal harm based on human data. Oral contraceptive use in early pregnancy is associated with an increased risk of congenital anomalies, particularly cardiovascular and limb defects.
2nd trimesterAvoid use during second trimester due to potential adverse effects on fetal development, including possible masculinization of female fetus with progestogens.
3rd trimesterAvoid use during third trimester as exposure to progestogens may cause genital abnormalities in the fetus.

Clinical note

Comprehensive clinical and safety monograph for SYEDA (SYEDA).

Placental transferBoth ethinyl estradiol and drospirenone cross the placenta. The transfer is significant, achieving fetal concentrations approximately 50-80% of maternal levels.
BreastfeedingEthinyl estradiol and drospirenone are excreted in breast milk in small amounts. Use during breastfeeding may reduce milk production and quality. Not recommended for nursing mothers until weaning is complete.
Lactation RatingL3 (Moderately Safe)
Teratogenic RiskFDA Pregnancy Category X. First trimester: high risk of neural tube defects, cardiac anomalies, and cleft palate. Second and third trimesters: risk of fetal adrenal suppression, virilization of female fetuses if androgenic progestins are present. Contraindicated in pregnancy due to teratogenicity and fetal harm.
Fetal MonitoringMonitor for signs of pregnancy if sexually active; perform pregnancy test before initiation and monthly. Monitor for thromboembolic events, hypertension, depression, and liver dysfunction. Fetal monitoring not applicable as drug is contraindicated in pregnancy.
Fertility EffectsSuppresses ovulation; intended for contraception. Reversible upon discontinuation. No permanent effects on fertility, but may delay return to ovulation post therapy.

Warnings & precautions

■ FDA Black Box Warning

Cigarette smoking increases the risk of serious cardiovascular events from combination oral contraceptive use. Risk increases with age and heavy smoking (≥15 cigarettes/day), particularly in women over 35. Women over 35 who smoke should not use combination oral contraceptives.

Side Effect Profile

Serious Effects

Absolute Contraindications

Thrombophlebitis or thromboembolic disordersHistory of deep vein thrombosis or pulmonary embolismCerebrovascular accidentCoronary artery diseaseKnown or suspected pregnancyLiver disease or impaired liver functionUndiagnosed abnormal uterine bleedingKnown or suspected breast carcinomaEstrogen-dependent neoplasiaHypersensitivity to any component

Clinical Precautions

PrecautionsThromboembolic disorders and other vascular events, cardiovascular disease, liver disease, hypertension, gallbladder disease, carbohydrate and lipid metabolism effects, headache, bleeding irregularities, depression, and use in women with hereditary angioedema.
Food/DietaryNo known food interactions. Grapefruit juice may reduce metabolism of ethinyl estradiol, but effect is not clinically significant. Avoid concurrent use with St. John's Wort, which induces CYP3A4 and reduces contraceptive efficacy.

Clinical Tips & Counseling

Clinical PearlsSYEDA (drospirenone/ethinyl estradiol) is a combined oral contraceptive. Use in women with renal impairment is contraindicated due to drospirenone's antimineralocorticoid effect. Monitor potassium levels in patients on NSAIDs, ACE inhibitors, or potassium-sparing diuretics. Increased risk of venous thromboembolism (VTE) compared to levonorgestrel-containing pills. Avoid in patients with migraine with aura, history of VTE, or breast cancer. Do not use in patients with liver tumors or acute hepatitis.
Patient AdviceTake one tablet daily at the same time, regardless of meals. Missing a dose increases pregnancy risk. · Use backup contraception (e.g., condoms) for 7 days if you miss one or more active pills. · Common side effects include nausea, breast tenderness, and spotting; these usually improve after 1–3 cycles. · Do not smoke while taking this medication, especially if over 35, due to increased risk of blood clots. · Immediately report symptoms of VTE: sudden leg swelling/pain, chest pain, shortness of breath, or vision changes. · This medication does not protect against HIV or other sexually transmitted infections.

SYEDA Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

ADQUEYAFIRMELLEALTAVERAALYACEN 1/35ALYACEN 7/7/7

External sources

DailyMed (NIH) PubMed OpenFDA