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Everything You Need to Know About Postinor-2 Pills

November 18, 2020

“Did my Postinor-2 pills work?” For a lot of women, using emergency birth control like Postinor-2 is an important part of their sexual life. But many ladies end up extremely anxious about them – unsure if the pills will work as they may not have taken them correctly. Knowing how to take them to make sure they’ve worked is important.

Read this article to learn essential points about using this medication.

When to Take Postinor-2 Pills

Firstly, you may need emergency birth control in any of the following scenarios to avoid an unplanned pregnancy:

  • when you have sex without using any contraceptive or birth control method
  • if your method was unreliable – e.g. the condom tore or slipped off during sex
  • your withdrawal method did not work
  • your coil/IUD fell out
  • after accidentally having sex during your fertile period
  • missing your regular contraceptive methods – failing to take two or three days of your pill
  • if you experience a sexual assault (rape).

Postinor-2 contains the human-made hormone Levonorgestrel. The pack usually includes one blister sheet containing two identical, white and round tablets.

How Postinor-2 Pills Work

Next, let’s look at how Postinor-2 affects the body. The method works by delaying the process of ovulation, where a mature egg is released from the woman’s ovary.

In addition, it makes the liquid in the womb (cervical mucus) thicker so that sperm cannot easily reach the egg; and can also prevent the egg, if fertilised, from implanting within the womb.

Therefore, it is an effective method for preventing pregnancy IF taken in the recommended way.

How To Be Sure Postinor-2 Pills Work After Taking Them

How to be sure Postinor-2 Pills Work

  • #1. Prepare in advance where you can. If you are sexually active and NOT on a regular form of contraception – get and keep a box of the Postinor-2 pills at home. While this is not always possible, it is true that having tablets to hand when you need them is ideal.
    • The next best thing is to get them as soon as possible after sex.
  • #2. Take the FIRST tablet as soon as possible after sex. It doesn’t matter which, as they are both the same.
    • But it would be best if you realise that the SECOND tablet is due TWELVE hours after you take the first. Therefore, schedule your first one so you can take the second one 12 hours after without missing it or delaying the dose. (This could happen if the time for the second dose comes when you are asleep). Don’t take the two pills at the same time.
  • #3. You can take Postinor-2 at ANY time during your menstrual cycle.
    • It is most effective when you take it before ovulation, but as you see above, it can also affect sperm movement and egg implantation.
  • #4. Postinor-2 is not an abortion treatment. If you think you may be pregnant, you should not use the medication. 
  • #5. If you can’t use the tablet straight away after sex, then do so as soon as practically possible – or consider another method of emergency birth control.
    • This is because: Postinor prevents pregnancy when taken within 72 hours of unprotected intercourse.
    • We think that overall, Postinor-2 will prevent 95% of expected pregnancies if taken within the first 24 hours, reducing to 58% if taken between 48 hours and 72 hours after unprotected intercourse. 
  • #6. Postinor-2 is generally safe, BUT there are specific scenarios when you shouldn’t use it:
    • if you are pregnant or have previously had unprotected intercourse more than 72 hours earlier in the same menstrual cycle, as you may already be pregnant.
    • you are experiencing vaginal bleeding for which the reason is not known.
    • if you have breast cancer.
    • you are allergic to any of the ingredients of the tablets (read the product leaflet).
    • if the pills do not look quite right (fake drugs).

Tips to help your Postinor-2 Pills Work Properly

  • #7. Can you take Postinor-2 when on other medicines?
    • It is useful for you to know that some drugs may prevent Postinor-2 from working correctly – or Postinor-2 may affect the way other medicines work. Some examples of drugs which may interfere with it working are:
      • Drugs used to treat epilepsy (for example, Barbiturates, Primidone, Phenytoin, and Carbamazepine).
      • Medications used to treat tuberculosis (for example, Rifampicin, Rifabutin).
      • Treatment for HIV infection (e.g. Ritonavir).
      • A medicine used to treat fungal infections (Griseofulvin).
      • Herbal remedies containing St John’s wort (Hypericum perforatum)
  • #8. Things may go wrong after taking the tablets.
    • Vomiting: If you vomit within two hours of taking either of the pills, you should repeat the tablet.
    • Suppose you vomit ‘dose one’, repeat it and take ‘dose two’ 12 hours after the new tablet. If you vomit only ‘dose two’, only repeat ‘dose 2’. 
    • To avoid nausea and vomiting, take the medication after food to reduce this side effect.
    • Bleeding: You may experience some spotting or bleeding within two to three days after taking the tablet.
    • Your next period usually starts within a week from your expected date after taking the pills. However, if your period is more than seven days late, it is recommended to get a pregnancy test.
    • If you experience a heavy or extended period of bleeding or very bad stomach pain, you should consult your doctor.​​​
    • Other side-effects:
      • Headache (you may take Paracetamol (Panadol, Tylenol, or Acetaminophen) to manage the headache.)
      • Breast pain or tenderness
      • Dizziness, Fatigue (Avoid activities that require mental alertness and avoid using heavy machinery).
  • #9.  Some manufacturers recommend you should not have more than four tablets of Postinor-2 in one cycle. It would be best if you did not use it as a regular form of contraception as it is meant only for emergency use.      
  • #10. Conditions like Breast Cancer, Heart Disease, Diabetes Mellitus, or Liver Disease may make it unsuitable for you to take Postinor-2 safely – please speak with a medical professional if you have any of these.
    • If you have bowel conditions like Crohn’s Disease, Ulcerative colitis or experience severe diarrhoea, this may not be an effective form of contraception as you cannot absorb the drug properly through your bowels. 
    • If you are overweight, the pill may not work as well for you as it will in women who are not.
      • Women who weigh over 70kg or have a BMI greater than 26kg/m2 can use an alternative form of contraception. If this is not available, then a ‘double dose’ of Postinor-2 can be taken.
      • This means you would take two tablets at the first dose and another two tablets 12 hours later.

Key Takeaways

These are important points to note if you want the postinor-2 pills to work properly. It’s also useful to note that this medication does not protect against HIV infection (AIDS) or other sexually transmitted infections.

Have you found these tips useful – or had any problems with how postinor-2 pills work? Let us know in the comments below.

More Reading


Editing By AskAwayHealth


All AskAwayHealth articles are written by practising Medical Practitioners on a wide range of healthcare conditions to provide evidence-based guidance and to help promote quality healthcare. 

The advice in our material is not meant to replace the management of your specific condition by a qualified healthcare practitioner.
To discuss your condition, please contact a health practitioner or reach us directly here.

Image Credits – Canva

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