Generic substitution (switching) is the replacement of one medicinal product by another, and only if the conditions set by applicable legal regulations are observed:

• the same active ingredient,
• the same route of administration,
• same dosage form.

The pharmacist can make a substitution only with the express consent of the patient and after a careful check of the conformity of the substitute medicinal product with the prescribed one.

Among the most common reasons are drug shortages in the market, which are caused by complications in production, distribution difficulties or an unpredictable increase in demand.

The advantage of a generic medicinal product is the provision of patient treatment even in the event of unavailability of the prescribed medicinal product.

A generic substitution cannot be made if:

• the doctor does not agree to the substitution and states "do not substitute" on the prescription (does not apply in the case when it is necessary to issue it immediately),
• the prescribed medicinal product is irreplaceable and the generic medicinal product is not registered.

However, there are also medicinal products that should not be confused. These include, for example:

• immunosuppressants,
• antiepileptic drugs,
• antiarrhythmic drug,
• thyroid hormones etc.

In this case, generic substitution could mean a quantitative change in effect or the occurrence of side effects.

It is also inappropriate to confuse local medicinal forms (ointments and creams), where the ointment base plays a large role in the permeability of the medicinal substance through the skin barrier.

Free according to the web portal of the Czech Pharmaceutical Chamber and SÚKL, 24/11/2022