Medroxyprogesterone (MPA): What it is and why people take it

Medroxyprogesterone, often called MPA, is a synthetic form of the hormone progesterone. You’ll see it as an oral pill (brand name Provera) or as an injection (Depo‑Provera). People use it for birth control, to treat irregular bleeding, for hormone therapy after menopause, or to manage conditions like endometriosis. It’s not the same as natural progesterone, so the effects and side‑effect profile can differ.

How people use medroxyprogesterone

The injection is usually given every 12–13 weeks. The common IM dose is 150 mg; there’s also a 104 mg subcutaneous option for some patients. For oral use, typical short courses for abnormal bleeding are 5–10 days of 5–10 mg daily. For hormone replacement, doctors often prescribe lower daily doses like 2.5–5 mg alongside estrogen. Always follow your prescriber’s exact plan — doses change by reason and patient history.

If you’re starting the injection for contraception, timing matters. If given during the first 7 days of a normal menstrual cycle, it usually protects right away. If given later, use backup contraception (condoms) for seven days. Missed oral pills are handled differently; check with your provider for the right steps based on how many doses you missed.

Safety, side effects, and what to watch for

Common side effects are changes in bleeding patterns, weight gain, headaches, and mood swings. The shot can cause irregular spotting for months, and some people stop bleeding regularly. A known risk with long‑term use of Depo‑Provera is reduced bone mineral density. Most bones recover after stopping, but if you plan more than two years on the shot, talk to your doctor about bone health and alternatives.

Medroxyprogesterone can affect blood sugar and mood. If you have diabetes, depression, or a history of blood clots, mention that before starting. Some drugs — like certain seizure medicines and rifampin — can make medroxyprogesterone less effective. Also, it’s not safe if you are pregnant. If you’re breastfeeding, discuss timing with your clinician; many providers consider it an option but will weigh benefits and risks.

Store pills at room temperature away from moisture. Injections are given by a clinician; do not try to self‑inject unless trained and prescribed a self‑administered product. If you notice severe symptoms such as chest pain, shortness of breath, severe leg pain, sudden vision changes, or intense abdominal pain, seek immediate medical care.

Want to switch or stop? Talk to your provider about how fertility may return. After the Depo shot, it can take several months (sometimes longer) for regular ovulation to come back. If pregnancy is a goal soon, consider alternative methods that allow quicker return of fertility.

If you have questions about brands, dosing schedules, or side effects, your pharmacist and prescriber are good resources. Use licensed pharmacies, get a proper prescription, and keep a simple record of injection dates or pill start times so you can keep track easily.