Which Drug Delays Your Period? A Pharmacological Guide

October 12, 2025 •

4 min read

An estimated 14% to 25% of women experience irregular menstrual cycles, and many seek ways to manage their timing for life events. If you are wondering which drug delays your period, the most common prescription is a synthetic hormone called norethisterone.

Quick Summary

For those not on hormonal contraception, the primary drug for delaying a period is norethisterone. It works by keeping progesterone levels high to prevent the uterine lining from shedding. Other options include using combined contraceptive pills back-to-back.

Key Points

Primary Medication: Norethisterone (a synthetic progesterone) is the main prescription drug used to delay periods for those not on hormonal contraception.
Mechanism of Action: It works by keeping progesterone levels artificially high, which prevents the shedding of the uterine lining.
Usage: It is typically taken multiple times daily, starting a few days before an expected period, for a limited duration to achieve the desired delay.
Alternative Method: People using combined contraceptive pills can often delay their period by skipping the 7-day hormone-free break and starting a new pack.
Important Warning: Norethisterone is NOT a contraceptive and does not protect against pregnancy; alternative contraception must be used.
Consultation is Key: Norethisterone is a prescription-only medicine and is unsuitable for individuals with a history of blood clots, certain cancers, or liver problems.
Side Effects: Common side effects can include nausea, bloating, breast tenderness, and mood changes. A serious risk is an increased chance of blood clots.

Understanding the Menstrual Cycle and Period Delay

The menstrual cycle is a complex process regulated by fluctuations in hormone levels, particularly estrogen and progesterone. Menstruation, or a period, occurs when the levels of progesterone drop, signaling the body to shed the uterine lining. Many individuals may seek to delay their period for various reasons, such as vacations, special events, or athletic activities, where having a period would be inconvenient. The principle behind delaying a period using medication involves maintaining hormone levels to prevent this shedding process.

Which Drug Delays Your Period? The Primary Option

For individuals who are not currently using a combined oral contraceptive, the medication most commonly prescribed to delay a period is norethisterone, which is also known as norethindrone in some regions. This drug is a synthetic version of the naturally occurring hormone progesterone. Norethisterone is a prescription-only medication and is available under various brand names, including Utovlan and Primolut N.

How Norethisterone Works

Norethisterone functions by keeping the body's progesterone levels elevated beyond the point where they would naturally drop, triggering menstruation. By maintaining these high levels, the uterine lining remains intact, thereby delaying the onset of bleeding. Typically, a period will begin a few days after discontinuing the medication.

Using Norethisterone for Period Delay

To effectively delay a period using norethisterone, the medication is typically started a few days before menstruation is expected. It is important to follow the specific instructions provided by a healthcare professional regarding when to begin taking the tablets and how frequently to take them. Taking the medication too close to the expected start date of your period may reduce its effectiveness and could result in breakthrough bleeding or spotting. Norethisterone can be taken for a limited time to achieve the desired delay. A critical point to remember is that norethisterone is not a method of contraception and will not protect against pregnancy.

Other Hormonal Methods for Delaying Menstruation

Individuals who are already using certain types of hormonal birth control may have options to delay their period without requiring a separate norethisterone prescription.

Combined Oral Contraceptives (The Pill)

If you are using a monophasic combined contraceptive pill, where each active pill contains the same dose of hormones, you can often delay your period by skipping the hormone-free interval or the placebo pills and immediately starting a new pack of active pills. While it may be possible to take multiple packs back-to-back, this could potentially increase the likelihood of experiencing side effects such as bloating or breakthrough bleeding. This method is generally not effective with progestogen-only pills (mini-pills) or phasic pills that have varying hormone levels throughout the cycle.

Other Hormonal Contraceptives

Contraceptive Patch: Skipping the usual patch-free week and applying a new patch can delay menstruation.
Vaginal Ring: Omitting the ring-free interval and inserting a new ring immediately can also postpone a period.

Comparison of Period Delay Methods


Method	How it Works	How to Use for Delay	Contraceptive?	Typical Delay
Norethisterone	Artificially maintains high progesterone levels to prevent uterine shedding.	Typically started a few days before expected period and taken multiple times daily as prescribed.	No	Limited duration based on prescription
Combined Pill	Maintains hormone levels by skipping the hormone-free break.	Skip the hormone-free break/placebo pills and start the next pack immediately.	Yes	The length of the next pill pack (approx. 21 days)
Contraceptive Patch	Maintains hormone levels by skipping the patch-free week.	Apply a new patch immediately instead of having a patch-free week.	Yes	The length of the next patch cycle (3 weeks)

Potential Side Effects and Risks

As with any medication, norethisterone can be associated with side effects. Common side effects may include nausea, bloating, tenderness in the breasts, headaches, and changes in mood or sex drive. While less common, more serious risks can include an increased risk of blood clots (thrombosis), particularly for individuals with existing risk factors. It is essential to discuss potential side effects and risks with a healthcare provider before taking norethisterone.

Who Should Avoid Period Delay Pills? (Contraindications)

Norethisterone is not suitable for all individuals. You should not take this medication if you have certain medical conditions or circumstances. These may include:

Pregnancy or breastfeeding
A personal or family history of blood clots (thrombosis)
Current liver problems or a history of a liver tumor
A history of heart attack or angina
Current or past breast cancer
Unexplained vaginal bleeding

A thorough consultation with a healthcare professional is necessary to evaluate your medical history, including factors such as blood pressure and BMI, to ensure that norethisterone is a safe option for you.

Conclusion

For individuals who are not using hormonal contraception, the primary drug prescribed to delay a period is norethisterone, a prescription-only medication that works by maintaining elevated progesterone levels. For those on certain types of combined hormonal birth control, skipping the hormone-free interval offers an alternative method to postpone a withdrawal bleed. Both approaches involve specific procedures, potential side effects, and contraindications. It is paramount to consult with a healthcare professional to determine the safest and most appropriate option based on your individual health profile and circumstances. They can provide personalized advice and ensure that any chosen method is suitable for you.

For additional information from a trusted health authority, consider visiting the NHS page on delaying periods.

Frequently Asked Questions

No, if your period has already begun, taking norethisterone will not stop it. It is designed to be taken before your period is due to start to be effective.

No, norethisterone is not a contraceptive and will not prevent pregnancy. You must use other forms of contraception, like condoms, while taking it.

Your period should typically start within a few days after you stop taking norethisterone tablets.

No, norethisterone is a prescription-only medication. You must have a consultation with a doctor or a qualified pharmacist to get a prescription.

If you forget to take a dose, you should take it as soon as you remember. However, if it is almost time for your next dose, skip the missed one. Do not take a double dose to make up for a missed tablet.

No, you cannot typically use the mini-pill to delay your period as there is no hormone-free break to skip. You might be able to take norethisterone in addition to your mini-pill, but you must consult a doctor first.

Common side effects can include nausea, headaches, breast tenderness, bloating, reduced libido, and mood changes. Spotting or breakthrough bleeding can also occur.