Zelleta is a progesterone-only pill (POP), also known as mini-pill, a type of oral contraceptives that contains a single active ingredient, a synthetic hormone which is able to mimic the functionality of naturally-occurring sex hormone progesterone when introduced into the female organism. As such, Zelleta contains desogestrel, but no synthetic oestrogen which is its main difference from combined contraceptive pills. However, exactly because of this, Zelleta can be safely used by women who are overly sensitive to oestrogen, as well as to women who are breastfeeding since progesterone will not affect the breast milk.

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How efficient is Zelleta?

The medical community more or less agrees progesterone only pills (POPs) or mini-pills are somewhat less reliable than their counterparts, combined hormonal contraceptives. But, this may be a bit misleading. It is not that progesterone-only birth control pills such as Zelleta are less effective, they just provide a single layer of protection as opposed to COCs which provide two, thanks to two active ingredients – synthetic progesterone and synthetic oestrogen. However, it is important to note that the protection provided by the presence of synthetic oestrogen is not considered to be reliable in itself, but only as an addition to protection provided by synthetic progesterone – something that is, obviously, also provided by Zelleta and other mini-pills (like Aizea for example). For more information on the specifics, please scroll down to the section of the text on Zelleta mechanism of action.

What can compromise the efficiency of Zelleta?

Another thing important to note is that the optimal levels of protection provided by Zelleta – advertised as 99% protection against pregnancy – can be successfully maintained only if you make sure that you are using Zelleta properly, exactly as instructed by your prescriber and in line with the guidelines provided in the official patient information leaflet that is issued within every pack of the birth control pill.

Likewise, in order to prevent any decrease in efficiency of Zelleta, you should get familiar with all the medications, remedies and foodstuffs which are known to impair the reliability of this contraceptive pill. Of course, in some cases you might not be able to avoid the medications in questions, so you should use additional barrier contraception during the period when efficiency of Zelleta is less than optimal. For more information on the exact substances that might cause problems as well as estimates on how long the impairment might last, please refer to the official patient information leaflet.

How does Zelleta work?

The secret to the efficiency and reliability of Zelleta is its active ingredient, a synthetic hormone, manmade bioequivalent to naturally-occurring sex hormone progesterone. Once introduced into the female organism, this compound will efficiently mimic the biochemical properties of progesterone.

Progesterone, in turn, plays a central role in directing, timing and triggering ovulation, the process of releasing the egg cell from the ovaries to the fallopian tubes. This happens once per month as the female body prepares for potential pregnancy. However, when birth control pills such as Zelleta are properly used, the increased levels of progesterone detected by the body due to the presence of norethisterone, will trick the body into “believing” that the ovulation already took place, so no egg cells will be released.

Can I buy Zelleta online in the UK?

Birth control pills, including mini-pills, are prescription-only medications in the UK, meaning that you can legally obtain them only with a valid prescription issued by a certified medical professional. However, this is not an obstacle for you to buy Zelleta online in the United Kingdom thanks to a number of online clinics operating within the country.

You will still be required to consult with a doctor, but you can now do that from the comfort of your home. In most cases, you will be required to fill in a specialised and detailed medical questionnaire that the doctor employed at the clinic will use in order to determine your suitability for using Zelleta. If everything checks out, the prescription will be issued and used to have the contraceptive pills sent from the partner pharmacy to the address you provided.

How to take Zelleta?

As was indicated, in order to ensure pregnancy prevention when using Zelleta, you should make sure to use this birth control pill exactly as instructed by your prescriber and in line with the guidelines provided in the official patient information leaflet that is issued within every pack of Zelleta.

Below, we will provide you with some of the most general guidelines that you should keep in mind when using this mini-pill. However, you should note that what follows is in no way a comprehensive guide – the list is there just for illustrative purposes, so you can get a better idea of what taking Zelleta might involve. As such, the list below can never be used as a substitute for the official information or the doctor’s advice.

  • Always take exactly as instructed by your prescriber and in line with the official guidelines
  • As is the case with most mini-pills, you should take Zelleta continuously, without any breaks
  • Be sure to take the pills at the same time each day
  • Take the tablets whole with water, without chewing or breaking them
  • If you forget to take a pill or are late more than three hours, consult the leaflet on how to proceed
  • When starting treatment, you should take the first pill on the first day of your period
  • If you have been using some other birth control pills or have recently been pregnant consult the leaflet on how and when to commence treatment
  • The arrows and labels on the strip containing the pills should help you stay on track with your treatment

What are Zelleta side effects?

Birth control pills are known to come with certain potential side effects. And while they certainly won’t manifest in everybody using the medication, it is still important to get familiar with them prior to commencing treatment so that you will be able to act accordingly.

It is very important to be able to differentiate between those side effects which might require you to stop treatment and seek immediate medical advice and those which are uncomfortable, but otherwise benign. The former group includes all signs and symptoms indicative of:

  • Allergic reaction
  • Breast cancer
  • Blood clot
  • Heart attack
  • Stroke

Other documented side effects include:

Common (1 in 10 women) Uncommon (1 in 100 women) Rare (1 in 1000 women)
·       Headaches

·       Mood swings

·       Loss of libido

·       Weight fluctuations

·       Nausea

·       General malaise

·       Breast pain

·       Missing periods

·       Vaginal infection

·       Hair loss

·       Ovarian cysts

·       Painful periods

·       Drowsiness

·       Eye irritation



·       Skin rash

·       Hives

·       Erythema nodosum







Please note that this is not a complete list of all documented side effects. For a more comprehensive overview, please refer to the official patient information leaflet that is issued within every pack of Zelleta.