Contemporary coordinative chemistry is still searching new substances that might constitute good ligands for transient metal ions: Cu(II), Ni(II), Co(II), Pt(II), Pd(II) oraz Cr(III). Pyrazole and its derivatives are able to make complexes with transient metal ions. There is a connection between pharmacological and chemical structure among pyrazole derivatives used in a medical treatment. A chemical division is coincident with a pharmacological division. Pyrazole-5 derivatives are mainly analgesic, antipyretic and less anti-inflammatory and diastolic but pyrazolidyn-3.5-dion derivatives are anti-inflammatory. The main part of non-steroid anti-inflammatory drugs belonging to pyrazolone derivates has a phenyl group at the first position. The activity and toxicity of this drugs are dependent on groups being at the fourth position. For example, the dimethylamino group makes aminophenazon antianalgetic, and yet is also responsible for a big toxicity. Azole derivatives are antimycotic and are ingredients of some ointments and creams. Chemical groups at the fourth position may determine the activity and the toxicity. These days a great attention is paid on a synthesis which is linking pyrazole and ions of platinum Pt(II) and palladium Pd(III) due to anticancer properties but pharmacology is not known very well.