Guide
Brand or generic — what a generic medicine is
Prepared by the LekCheck team · Last reviewed: 2026-07-21 · How we create our content
A generic medicine contains the same active ingredient, in the same dose and pharmaceutical form, as the original (branded) product whose patent has expired. To be authorised for sale it must demonstrate bioequivalence — that the body absorbs it in a comparable way. The price difference is often substantial, because the generic's manufacturer does not carry the costs of the original development. Below we explain how to compare them in an informed way.
This guide was prepared by the LekCheck team and has not been reviewed by a doctor or pharmacist. This article is for general information only and is not medical advice, diagnosis, or treatment. Do not start, stop, or change any treatment without consulting a doctor or pharmacist.
How generic medicines are approved
In Bulgaria medicines are authorised by the Bulgarian Drug Agency (BDA), and many products also go through the European Medicines Agency (EMA). A generic must demonstrate the same amount of active ingredient and bioequivalence to the original. The excipients (fillers, colourants) can differ — which matters for allergies or intolerances, e.g. to lactose.
Why the price differs
The original manufacturer invests in development and clinical trials and recoups those costs during patent protection. Once it expires, other manufacturers can produce the same ingredient, competition grows and the price falls. That is why the same medicine, in terms of active ingredient, can cost differently depending on brand, manufacturer and pharmacy.
How to compare brand and generic on LekCheck
Every product on LekCheck lists its active ingredient when known. From the product page you can open the ingredient's page and see all products containing it — brands and generics — with current prices from online pharmacies. The "Cheaper alternatives" section on the product page shows cheaper in-stock products with the same ingredient.
When the choice is not just about price
For prescription medicines, switching between brand and generic is decided by the doctor or pharmacist. Different excipients, forms (tablet, capsule, syrup) and strengths may not be interchangeable for a specific patient. This article is informational — if in doubt, always consult a pharmacist or doctor.
Commonly used active ingredients
Pick an ingredient to see products and prices.
Frequently asked questions
Does a generic work the same way as the original?
A generic contains the same active ingredient in the same dose and demonstrates bioequivalence during approval, so a comparable effect is expected. Individual differences are possible (e.g. due to the excipients), which is why for prescription medicines a switch is discussed with a doctor or pharmacist.
Why are generic medicines cheaper?
Because their manufacturer does not carry the costs of the original development and clinical trials, and enters the market after patent expiry, when there is competition. A lower price does not mean lower manufacturing quality — production is controlled to the same standards.
How do I find out the active ingredient of my medicine?
It is printed on the pack and in the leaflet, usually beneath the trade name. On LekCheck it is shown on the product page when known, with a link to all products containing the same ingredient for price comparison.