Sronyx 28 Day Side Effects: What You Need to Know

Every medication comes with potential side effects, and Sronyx 28 Day is no exception. As a combined oral contraceptive containing Levonorgestrel 0.1 mg and Ethinyl Estradiol 0.02 mg, Sronyx carries the same side effect profile as other low-dose birth control pills. Most side effects are mild and go away within the first few months, but some require immediate medical attention.

This guide covers exactly what to expect — and when to call your doctor.

What Is Sronyx 28 Day?

Sronyx 28 Day is a monophasic combined oral contraceptive (COC) manufactured by Mayne Pharma. Each 28-day pack contains 21 white active tablets and 7 peach placebo tablets. It works by suppressing ovulation, thickening cervical mucus, and altering the uterine lining to prevent pregnancy.

Note: Sronyx has been discontinued by its manufacturer. If you're currently taking it or looking for it, equivalent generics like Vienva, Aubra, Lutera, and Aviane contain the same active ingredients at the same dose. The side effect information below applies to all of them.

Common Side Effects

These side effects are reported frequently, especially during the first 1–3 months of use. Most improve as your body adjusts:

• Nausea: One of the most common complaints. Taking your pill with food or at bedtime can help.
• Headache: Mild headaches are common, especially in the first few weeks.
• Breakthrough bleeding or spotting: Light bleeding between periods is very common in the first 1–3 packs. It usually resolves on its own.
• Breast tenderness: Swelling or soreness in the breasts, typically mild.
• Bloating: Some fluid retention is normal, particularly early on.
• Weight changes: Small fluctuations (usually 1–3 pounds) may occur, often related to water retention rather than fat gain.
• Mood changes: Some women experience mood swings, irritability, or depressive symptoms.
• Acne: Skin changes can go either way — some women see improvement, others notice breakouts initially.
• Decreased libido: A reduction in sex drive is reported by some users.
• Vomiting: Less common than nausea but can occur, especially if taken on an empty stomach.

If any of these side effects persist beyond 3 months or significantly affect your daily life, talk to your doctor. Switching to a different formulation sometimes helps.

Serious Side Effects

Serious side effects from Sronyx 28 Day are rare but can be life-threatening. Seek immediate medical attention if you experience any of the following:

• Blood clots (deep vein thrombosis or pulmonary embolism): Symptoms include sudden leg pain or swelling, chest pain, shortness of breath, or coughing up blood. Combined oral contraceptives increase the risk of blood clots, though the absolute risk remains low (about 3–9 per 10,000 women per year on COCs vs. 1–5 per 10,000 not on COCs).
• Stroke: Watch for sudden severe headache, confusion, vision changes, numbness or weakness on one side of the body, or difficulty speaking.
• Heart attack: Symptoms include chest pain or pressure, pain radiating to the arm or jaw, shortness of breath, and cold sweats.
• Liver problems: Signs include yellowing of the skin or eyes (jaundice), dark urine, severe abdominal pain in the upper right area, or unusual fatigue.
• Gallbladder disease: Severe abdominal pain, nausea, and vomiting may indicate gallbladder issues.
• High blood pressure: COCs can raise blood pressure in some women. Regular monitoring is recommended.
• Retinal thrombosis: Rare. Symptoms include sudden partial or complete loss of vision.

The Boxed Warning: Smoking + Birth Control

The FDA requires a boxed warning — the strongest type of safety warning — on all combined oral contraceptives:

Cigarette smoking increases the risk of serious cardiovascular side effects from oral contraceptive use. This risk increases with age and with the number of cigarettes smoked (15 or more per day is especially dangerous) and is quite marked in women over 35 years of age. Women who use oral contraceptives should not smoke.

If you smoke and are over 35, your doctor should not prescribe Sronyx or any combined oral contraceptive.

Who's Most at Risk for Serious Side Effects?

Certain groups face higher risks when using combined oral contraceptives:

• Women over 35 who smoke — significantly increased cardiovascular risk
• Women with a history of blood clots (DVT, PE) — COCs are contraindicated
• Women with migraine with aura — increased stroke risk
• Women with uncontrolled hypertension — COCs can worsen blood pressure
• Women with diabetes with vascular complications
• Women with a history of breast cancer or estrogen-sensitive cancers
• Women with active liver disease or liver tumors

Your doctor should review these risk factors before prescribing. For a full list of contraindications, see our complete guide to Sronyx 28 Day.

How to Manage Common Side Effects

Here are practical tips for dealing with the most frequent complaints:

Nausea

• Take your pill with food or right before bed
• Avoid taking it on an empty stomach
• If nausea persists after 3 months, ask your doctor about switching formulations

Breakthrough Bleeding

• This is very common in the first 1–3 packs — don't panic
• Take your pill at the same time every day (consistency helps)
• Don't skip pills, as this makes spotting worse
• If bleeding persists beyond 3 packs, see your doctor

Headaches

• Over-the-counter pain relief (ibuprofen, acetaminophen) is generally safe
• Stay hydrated and maintain regular sleep
• If you develop severe headaches or migraine with aura, stop taking the pill and call your doctor immediately — this could indicate increased stroke risk

Mood Changes

• Track your moods for the first few months to identify patterns
• If you experience persistent depression or severe mood swings, talk to your provider — a different formulation or non-hormonal method may be a better fit

Bloating and Weight Changes

• Mild bloating usually resolves within 2–3 months
• Regular exercise and limiting sodium can help
• Significant weight gain is uncommon with low-dose pills like Sronyx

Final Thoughts

Most women tolerate Sronyx 28 Day and its equivalent generics well. The common side effects — nausea, spotting, headaches, breast tenderness — are typically mild and temporary. The serious side effects, while rare, are real and warrant awareness.

The key takeaways:

• Give your body 2–3 months to adjust before deciding the pill isn't working for you
• Don't smoke while taking combined oral contraceptives
• Know the warning signs of blood clots, stroke, and heart attack
• Talk to your doctor if side effects don't improve or significantly impact your quality of life

If you're having trouble finding Sronyx or an equivalent generic, Medfinder can help you locate pharmacies with stock near you.