Tablet subdivision is a common practice among patients and doctors. Tablets can be divided into smaller parts to obtain the desired dose and adjust this dose to the actual needs of the patient. Manipulation of the drug dose is aimed at improvement of the effectiveness of pharmacotherapy, reduction of the occurrence of dose-dependent side effects, or minimization of treatment costs.

The aim of the study is to discuss the available data concerning the problem of tablets subdivision, the precision of this practice and its safety for the patient.

The following databases were searched: PubMed, Google Scholar, Embase using the appropriate key words: „splitting”, „subdivision”, „tablets”, „halves of tablets” (last search in June 2020).

State of knowledge:
Tablet subdivision is performed in the case of drugs requiring a gradual increase in the dose, and then, after a period of appropriate treatment, slowly reducing the dose in order to avoid the increased effects of the withdrawal syndrome resulting from the specific action of these drugs. This applies mainly to antidepressants, neuroleptics, hypnotics and sedatives, as well as anxiolytics used in psychiatric treatment. Parts of tablets are also easier to swallow, which is especially important for patients with swallowing problems (dysphagia). It is estimated that almost half of the population is unable to swallow tablets in full, mainly geriatric patients, children and patients with mental disorders.

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