Susten SR 400 mg (Progesterone) Tablet

Introduction About Susten SR 400 mg

Susten SR 400 mg is a sustained-release progesterone product that gradually releases progesterone over time.

Progesterone is a natural hormone that helps regulate the menstrual cycle and supports the uterine lining.

Some clinicians prescribe progesterone when the body is not making enough on its own, or when stable progesterone levels are needed as part of a specific treatment plan.

What Susten SR 400 mg is commonly used for

Depending on your diagnosis and your prescriber’s plan, sustained-release progesterone may be used for:

• Luteal phase support in certain fertility or assisted reproduction protocols
• Hormonal support in early pregnancy, when a clinician believes progesterone support is appropriate
• Hormone therapy support for people using estrogen, where a progestogen may be needed to help protect the uterine lining (for those who have a uterus)
• Cycle regulation in selected cases where progesterone therapy is part of the approach

The exact reason you are prescribed it matters because dosing schedules can look very different from one person to another.

How it works in the body

Progesterone helps prepare and maintain the endometrium (the lining of the uterus). In simple terms, it can shift the lining into a more stable state, less likely to shed at the wrong time.

In hormone therapy settings, progesterone is often used alongside estrogen to reduce the risk of estrogen-related overgrowth of the uterine lining.

The “SR” (sustained-release) design aims to provide steadier levels than immediate-release products, though how it feels can still vary from person to person.

How it is usually taken

Susten SR 400 mg is taken by mouth exactly as prescribed. Some people are told to take it in the evening because progesterone can make you feel drowsy, but you should follow the schedule your clinician gives you. Try to take it the same way each time (with or without food), as consistency can help reduce side-to-side variation in absorption.

Do not change your dose on your own, even if symptoms improve or you start feeling side effects. With hormone medicines, small adjustments can make a real difference, and your prescriber may be timing your dose around a cycle, lab results, or a fertility protocol.

Side effects you might notice

Not everyone gets side effects, but progesterone can cause symptoms that feel like PMS. Commonly reported effects include:

• Sleepiness or fatigue
• Dizziness
• Breast tenderness
• Bloating or stomach discomfort
• Headache
• Mood changes

Some people also notice spotting or changes in bleeding patterns, depending on why it was prescribed and whether estrogen or other hormones are also being used.

When to contact a clinician urgently

Stop and get medical help right away if you develop symptoms that could signal a serious problem, such as:

• Signs of a severe allergic reaction (swelling, hives, trouble breathing)
• Chest pain, shortness of breath, and coughing blood
• Sudden severe headache, weakness on one side, trouble speaking, or vision changes
• Yellowing of the skin or eyes (possible liver issue)

These are not expected effects, but they matter because progesterone and other hormone therapies can affect clotting risk in certain people, and liver health is also important for hormone metabolism.

Important precautions and interactions

Before starting Susten SR 400 mg, your prescriber should know your history, especially if you have had blood clots, stroke, certain cancers, unexplained vaginal bleeding, or liver disease.

Also, share a full medication list. Some medicines can change how hormones are processed, including certain anti-seizure medicines, some antibiotics, and herbal supplements like St. John’s wort.

If you are using other hormone products (estrogen, progestins, fertility medications), coordination matters.

Available Strengths

Susten SR is commonly seen in multiple strengths depending on the market and supplier. You may find options such as:

• Susten SR 200 mg
• Susten SR 300 mg
• Susten SR 400 mg

Progesterone products are generally available in 100 mg and 200 mg strengths (often as immediate-release micronized progesterone). Availability can vary, so confirm the exact strength and formulation on the package and prescription.

Substitutes

If Susten SR 400 mg is not suitable or not available, clinicians may consider alternatives based on the goal of treatment, the preferred route, and tolerance:

Same hormone (progesterone), different brands/forms

• Prometrium (micronized progesterone) or generic progesterone capsules (often immediate-release)
• Utrogestan (micronized progesterone) (brand availability depends on country)
• Vaginal progesterone options such as Crinone gel or Endometrin inserts (often used in fertility settings)
• Progesterone in oil injections (used in some fertility protocols)

Different progestogens (not identical to progesterone)

• Medroxyprogesterone acetate (Provera) and other synthetic progestins may be used for certain indications, but they are not the same as micronized progesterone. Your clinician decides based on your history and treatment goals.

FAQs

1. Is Susten SR 400 mg the same as regular progesterone capsules?

Not exactly. “SR” usually means sustained-release, designed to release medicine more gradually. Regular micronized progesterone capsules are often immediate-release. The dose may not be interchangeable without prescriber guidance.

2. How should I store Susten SR 400 mg?

Store it in a dry place at room temperature, away from direct heat and moisture. Keep it in the original packaging and out of reach of children.

3. What should I do if I miss a dose?

Follow your prescriber’s instructions. If you do not have specific instructions, contact your pharmacy or clinician for advice, especially if the medication is part of a fertility or cycle-timed plan.

4. Can I drink alcohol while taking Susten SR 400 mg?

Alcohol can worsen drowsiness and dizziness that progesterone may cause. If you drink, consider limiting it and ask your prescriber what is safe for your situation.

5. Can Susten SR 400 mg affect my ability to drive or work?

It can. Some people feel sleepy, slowed down, or dizzy, especially when starting or after dose changes. See how you respond before driving, operating machinery, or doing safety-sensitive tasks.