Medroxyprogesterone Medications

Medroxyprogesterone Info

What Is Medroxyprogesterone?

Medroxyprogesterone is a synthetic progestogen - a man-made version of the natural hormone progesterone. It belongs to the class of hormonal medicines that mimic the effects of progesterone in the body. In Hong Kong, it is used in several branded and generic products, including Cycrin, Provera, and the generic preparation labelled simply as medroxyprogesterone.

Medications with Medroxyprogesterone

A number of formulations contain this active ingredient.

• Cycrin - available as oral tablets, often prescribed for menstrual-related conditions.
• Provera - supplied as tablets and sometimes as an injectable solution for longer-acting treatment.
• Medroxyprogesterone (generic) - sold under the ingredient name, typically in tablet form.

These products may differ in strength, with common tablet doses ranging from 2.5 mg to 10 mg, and may be combined with other hormones such as oestrogen in certain hormone-replacement regimens. All are approved for use in Hong Kong by the Pharmacy and Poisons Board and are listed on the Hong Kong Department of Health’s product registry.

What Does Medroxyprogesterone Treat?

Medroxyprogesterone is employed for several hormone-related conditions:

• Irregular menstrual cycles - helps restore a more regular pattern when periods are absent or unusually frequent.
• Amenorrhoea - stimulates a withdrawal bleed in women who have stopped menstruating, often after childbirth or during hormonal therapy.
• Endometriosis-related pain - reduces the growth of endometrial tissue outside the uterus, easing discomfort.
• Hormone-replacement therapy (HRT) - combined with oestrogen to protect the uterine lining in post-menopausal women.
• Certain types of cancer - in some protocols, a progestogen component is included to slow the growth of hormone-sensitive tumours (use is specialist-guided).

These uses are the primary approved indications in Hong Kong. The medication may also be prescribed off-label for other hormonal imbalances, but such decisions rest with the prescribing clinician.

How Medroxyprogesterone Works

When taken, medroxyprogesterone binds to progesterone receptors in the body, reproducing the natural hormone’s actions. This helps stabilise the uterine lining, regulates the menstrual cycle, and counteracts the effects of excess estrogen. The effect usually begins within a few days of starting therapy, although full cycle regulation may take several weeks.

Safety Information

Common Side Effects

• Light spotting or brief bleeding between periods
• Mild headache or feeling of tiredness
• Nausea or minor stomach upset
• Breast tenderness or slight swelling

These reactions are usually temporary and resolve without medical intervention.

Serious Reactions

• Severe allergic response (e.g., swelling of the face, throat, or tongue, difficulty breathing) - treat as an emergency
• Sudden, unexplained bruising or bleeding
• Unusual abdominal pain that persists

If any of these symptoms appear, seek immediate medical help.

Who Should Be Cautious

• Individuals with a history of blood-clotting disorders, liver disease, or certain cancers should discuss use with a qualified professional.
• Pregnant women should avoid medroxyprogesterone unless its benefit outweighs potential risk, as advised by a specialist.
• People known to be allergic to medroxyprogesterone or any of its excipients should not use these medicines.

Interaction Awareness

Medroxyprogesterone may interact with:

• Other hormonal agents - co-administration may require dose adjustments.
• Antifungal or antibiotic medicines that affect liver metabolism.
• Alcohol - excessive intake can increase the risk of liver strain.

Lifestyle factors such as driving or operating machinery are not generally affected, but individuals should be aware of how they personally respond to the medication. For a full list of possible interactions, refer to the specific product’s information leaflet.

What to Know Before Using

Store tablets or injectables at room temperature, away from moisture and direct sunlight. Typical courses last from a few weeks (for menstrual regulation) to several months (for hormone-replacement therapy), depending on the condition being treated. Always follow the instructions printed on the medication’s label, as formulations and strengths differ between Cycrin, Provera, and the generic product. For detailed usage, dosing, and administration, refer to the information provided with your specific medication.

Information Disclaimer

This article offers general educational information about medroxyprogesterone as an active substance used in various medicines. Its purpose is to help patients better understand the ingredient and the conditions it is used to treat. It is not a substitute for professional medical advice or for the specific instructions provided with individual products. Medicines containing medroxyprogesterone may differ in formulation, strength, and directions for use. Always consult the labeling of your particular medication and follow your healthcare provider’s guidance for complete information on proper use, dosage, and safety.