Zelleta Tablets

Desogestrel progestogen-only pills represent one of the most significant developments in oral contraception of the past three decades. Before desogestrel, every progestogen-only pill worked almost entirely through cervical mucus thickening, required tablet-taking within a strict 3-hour daily window, and did not consistently prevent ovulation. Desogestrel changed all three of those parameters simultaneously.

Zelleta is a desogestrel progestogen-only pill containing 75 micrograms per tablet. It is licensed in the United Kingdom for the prevention of pregnancy, manufactured by Morningside Healthcare Ltd, and taken as one tablet daily with no breaks between packs. It suppresses ovulation in approximately 97% of cycles according to the UK SmPC, carries a 12-hour missed pill window, and contains no oestrogen. This page covers what desogestrel at 75 mcg means in practice, who Zelleta suits, and what the prescribing process looks like.

Four desogestrel 75 mcg progestogen-only pills are currently licensed and available in the UK: Cerazette (Organon), Cerelle (Consilient Health), Feanolla (Gedeon Richter), and Zelleta (Morningside Healthcare). All four contain identical active ingredients at identical doses. All four follow the same continuous daily schedule. All four suppress ovulation in approximately 97% of cycles and carry a 12-hour missed pill window. FSRH guidance treats them as clinically interchangeable, and pharmacies dispense whichever version is in stock.

Knowing this matters practically. If your previous prescription was for Cerelle and your pharmacy supplies Zelleta, nothing clinically has changed. If your pack looks different from last time, it is the manufacturer that has changed, not the medicine.

What separates the desogestrel group as a whole from older norethisterone-based and levonorgestrel-based progestogen-only pills is significant. Norethisterone pills such as Noriday, and levonorgestrel pills such as Norgeston, both work primarily by thickening cervical mucus. They do not reliably suppress ovulation. Desogestrel at 75 mcg consistently inhibits the ovulatory cycle in the vast majority of cycles, making it pharmacologically closer in mechanism to a combined pill – but without oestrogen. This is why the 12-hour window is achievable: the contraceptive protection comes from ovulation suppression, not just from a time-sensitive mucus effect.

Desogestrel is a prodrug. After you take a Zelleta tablet, the digestive system converts desogestrel to its active form, etonogestrel. This is the same active compound delivered transdermally by the Evra contraceptive patch and released locally by the Nexplanon implant. Desogestrel tablets, the patch, and the implant all ultimately rely on etonogestrel to produce their contraceptive effect – they simply deliver it by different routes and at different doses.

How Etonogestrel Suppresses Ovulation

Etonogestrel acts on the hypothalamic-pituitary axis, suppressing the production of follicle-stimulating hormone and luteinising hormone. The luteinising hormone surge is the trigger for egg release. Without it, the ovary does not ovulate. In approximately 97% of cycles, this suppression is complete. In the remaining 3%, an egg may be released despite the progestogen exposure.

The 12-Hour Window: Why It Exists

Because the primary contraceptive mechanism is ovulation suppression rather than a time-sensitive cervical mucus effect, Zelleta does not require the strict 3-hour daily window that applies to Noriday and Norgeston. Etonogestrel levels in the bloodstream remain sufficient to maintain follicular suppression for a longer period than the threshold window for mucus-based contraception. The 12-hour window is therefore not a concession or a safety margin. It is a direct consequence of how desogestrel works.

Cervical Mucus and Endometrial Effects

Even in cycles where ovulation suppression is not complete, etonogestrel maintains a secondary contraceptive effect by thickening cervical mucus and altering the endometrial lining. The mucus effect creates an additional barrier to sperm penetration. The endometrial effect reduces the likelihood of implantation. Together, these secondary mechanisms provide contraceptive protection that extends beyond the 97% ovulation suppression rate.

One of the practical advantages of the desogestrel mini pill is the absence of a schedule. There are no 21-day active phases, no seven-day breaks, no phase sequences to follow. One tablet every day, continuously, starting the next pack immediately after the last tablet of the previous one. The schedule repeats indefinitely until you stop.

Getting Started

Starting on day 1 of your period provides immediate protection from the first tablet. Starting between days 2 and 5 of your cycle also works, but requires barrier contraception for the first two days.

Switching from a combined pill: take the first Zelleta tablet the day after the last active tablet from the previous pack. If your combined pill had inactive placebo tablets, take the first Zelleta after the last placebo. Use barrier contraception for two days.

Switching from another progestogen-only pill: start the day after the last tablet from the previous pack. No gap. Use barrier contraception for two days.

After childbirth: Zelleta can be started from day 21 post-delivery with immediate protection. Starting before day 21 requires barrier contraception for the first two days.

The Daily Habit

Take one Zelleta tablet at the same time every day. There are no colour changes, phase changes, or sequences to track. All tablets are identical. Swallow each tablet whole with water. If you vomit within two hours of taking a tablet or have a significant episode of diarrhoea, absorption may be incomplete. Treat this as a missed tablet.

If You Take a Tablet More Than 12 Hours Late

Under 12 hours late: take the tablet as soon as you notice. Continue at your usual time. Protection is maintained.

More than 12 hours late: take the missed tablet immediately. Take the next one at the usual time, even if two fall on the same day. Use a barrier method for the next two days.

If unprotected sex occurred during a period when Zelleta protection may have been reduced, contact your prescriber or pharmacist about emergency contraception. The sooner you seek advice, the more options are available.

Each Zelleta tablet contains desogestrel 75 micrograms. There is one strength. Every tablet is identical. One tablet taken daily, without breaks, provides the continuous etonogestrel exposure that suppresses ovulation.

Understanding 75 mcg Desogestrel in Context

The 75 mcg desogestrel dose in Zelleta is calibrated to produce circulating etonogestrel levels sufficient for consistent ovulation suppression. Compare this to other etonogestrel-based contraceptives:

1. Zelleta (and Cerazette, Cerelle, Feanolla): desogestrel 75 mcg orally, releasing etonogestrel after conversion
2. Nexplanon subdermal implant: delivers etonogestrel directly at approximately 60 to 70 mcg per day initially, declining over three years
3. Evra transdermal patch: delivers etonogestrel (as norelgestromin, a related compound) dermally alongside ethinylestradiol

These products use etonogestrel by different routes at different doses. What they share is the same active progestogen achieving ovulation suppression as the primary contraceptive mechanism. Zelleta provides the oral route at a dose established to deliver consistent suppression in clinical studies.

Supply and Interchangeability

Zelleta does not need to be treated as a unique supply line. If your pharmacy cannot supply Zelleta, Cerazette, Cerelle, or Feanolla are clinically equivalent substitutes. Switching between them requires no prescriber review and no adjustment to how or when you take the pill.

The most clinically relevant side effect conversation for anyone considering Zelleta is about bleeding. Not headache, not mood, not the list of possibilities. Bleeding. Because no other side effect of the desogestrel mini pill is as likely to affect whether a woman continues or stops taking it.

Bleeding Pattern: The Honest Picture

Desogestrel at 75 mcg suppresses ovulation and alters the endometrium. Both of these actions affect bleeding. What the endometrium does on Zelleta is unpredictable and highly individual. Some women stop having periods altogether within a few months. Some experience lighter, shorter bleeds. Some experience frequent irregular spotting, particularly in the first three to six months. There is no way to predict which category any individual woman will fall into before she starts. All of these outcomes are documented in the Zelleta SmPC and are considered expected responses to the preparation, not signs of a problem.

If you experience very heavy bleeding, bleeding that does not settle after the first few months, or bleeding that returns after an extended period of no bleeds, contact your prescriber to rule out other causes.

Etonogestrel and Androgen Receptors

One notable characteristic of etonogestrel is its very low androgenic activity. Unlike norethisterone, which binds weakly to androgen receptors, etonogestrel has high selectivity for the progesterone receptor with minimal androgenic effect. For women who have experienced acne or oily skin on norethisterone-based progestogen-only pills, this is clinically relevant. Zelleta is less likely to contribute to androgenic skin effects than norethisterone-based alternatives.

Other Reported Effects

1. Mood changes, including low mood or irritability
2. Reduced libido
3. Breast tenderness
4. Nausea
5. Headache
6. Ovarian cysts: follicular development may occur and produce temporary cysts, usually resolving without treatment

Signs Needing Urgent Attention

Contact emergency services or go to A&E immediately if you experience severe one-sided abdominal pain alongside a missed period or unusual bleeding – this may indicate an ectopic pregnancy. Also seek urgent help for sudden chest pain, difficulty breathing, severe headache, visual disturbance, or one-sided weakness.

Drug Interactions

Enzyme-inducing medicines reduce etonogestrel circulating levels, lowering contraceptive effectiveness. These include rifampicin, certain antiepileptics including phenytoin, carbamazepine, phenobarbital, and topiramate, some HIV antiretrovirals, and St John's Wort. Always declare every medicine and supplement to your prescriber at each consultation.

Progestogen-only pills are often the contraceptive conversation that begins when combined pills are no longer the right answer. Zelleta fits a wide range of circumstances where oestrogen is contraindicated, inconvenient, or simply not preferred.

Zelleta Is Not Suitable If You:

1. Have a current or previous diagnosis of breast cancer or any sex-hormone-sensitive malignancy
2. Have unexplained vaginal bleeding that has not been assessed by a clinician
3. Have severe liver disease or active liver tumours
4. Have a condition that significantly impairs oral medication absorption
5. Are allergic to desogestrel or to any of the tablet excipients

Zelleta Is Often the Right Choice If You:

1. Cannot use oestrogen-containing contraception for any clinical reason: migraine with aura, cardiovascular risk factors, a personal history of VTE, or breastfeeding a baby over six weeks old
2. Are a smoker aged 35 or over, for whom combined pills are contraindicated
3. Find the 3-hour timing requirement of norethisterone or levonorgestrel mini pills difficult to maintain and prefer the flexibility of a 12-hour window
4. Have experienced androgen-related skin effects on norethisterone-based pills and want to try a progestogen with lower androgenic activity
5. Prefer a simpler schedule with no phase changes, no breaks, and identical tablets throughout

A Note on Ectopic Pregnancy History

Women with a history of ectopic pregnancy should discuss this with their prescriber before starting Zelleta. While Zelleta suppresses ovulation in the majority of cycles, fertilisation remains possible in cycles where ovulation occurs. If a pregnancy does occur on Zelleta, there is a risk it could be ectopic. Your prescriber will weigh your personal history carefully and confirm whether Zelleta or a different contraceptive method is more appropriate for your circumstances.

At Pharmacy Planet, every prescription begins with a clinical consultation read by a registered prescriber. For Zelleta, the prescriber is assessing three things.

First: whether any of the absolute contraindications to progestogen-only contraception apply. The list is shorter than for combined pills – no oestrogen means no stroke risk from aura, no VTE risk from oestrogen, no restriction for smokers over 35 – but the prescriber still needs to confirm your health profile supports this method.

Second: whether Zelleta is the appropriate progestogen-only preparation for you, or whether a norethisterone or levonorgestrel alternative would be more suitable. The prescriber considers your previous pill experience, any androgenic side effect history, and how important the 12-hour window flexibility is to your daily routine.

Third: whether there is anything in your history that requires additional consideration, such as a previous ectopic pregnancy. The prescriber documents this and factors it into the recommendation.

The outcome of the consultation may be a prescription for Zelleta, a recommendation for a different progestogen-only preparation, a suggestion to consider a different contraceptive method entirely, or a referral for an in-person assessment. Repeat prescriptions follow the same individual review. There is no automatic renewal.

Store Zelleta below 25°C in a dry location away from direct light. Because Zelleta is taken every day with no breaks, you will move through packs more frequently than with a combined pill. Having a clear storage spot that connects to your daily tablet-taking routine helps maintain both the timing habit and the supply continuity.

Keep tablets in the original blister strip until you take them. All tablets are identical, so there is no sequence to preserve – but the foil protects from moisture and the pack label carries the expiry date. Check this date when you open each new pack.

Return unused or out-of-date tablets to a UK pharmacy. Pharmacies accept returned medicines for safe disposal under Duty of Care regulations, at no charge to you. Do not dispose of contraceptive tablets in household waste or flush them down the toilet.

This reference guide compares the contraceptive preparations available at Pharmacy Planet, grouped by delivery method and formulation type. Every preparation is a Prescription Only Medicine. A registered prescriber will review your individual health profile, contraceptive history, and risk factors before recommending any preparation. This table is a clinical reference, not a recommendation.

Progestogen-only pills contain no oestrogen and are taken every day with no break between packs. The table below compares commonly prescribed progestogen-only pills by missed pill window, primary contraceptive mechanism, and clinical characteristics. These differences are clinically significant and pills are not interchangeable without prescriber review.

Important: This comparison is for general information only and does not replace medical advice. A prescriber will decide which treatment is suitable for you following an online consultation.

The desogestrel mini pill is one of the most commonly prescribed contraceptives in UK primary care. That familiarity does not remove the clinical responsibility that comes with every prescription. A prescriber still needs to know your medical history, your previous contraceptive experience, any relevant drug interactions, and whether there are circumstances such as a history of ectopic pregnancy that require specific consideration. At Pharmacy Planet, that assessment happens every time.

If Zelleta is not the right preparation for your profile, the prescriber will say so and explain the reasoning. That is the consultation working as it should.

• Morningside Healthcare Ltd. Zelleta 75 microgram film-coated tablets – Summary of Product Characteristics. Available at: www.medicines.org.uk/emc. Accessed May 2026.
• Faculty of Sexual and Reproductive Healthcare (FSRH). Progestogen-Only Pills – Clinical Guidance. Available at: www.fsrh.org. Accessed May 2026.
• NHS. Progestogen-only pill (mini pill). Available at: www.nhs.uk/conditions/contraception/progestogen-only-pill. Accessed May 2026.
• British National Formulary (BNF). Desogestrel. Available at: bnf.nice.org.uk. Accessed May 2026.
• FSRH Clinical Effectiveness Unit. Progestogen-Only Methods and Ectopic Pregnancy. Available at: www.fsrh.org. Accessed May 2026.