Pixantrone is a novel anthracenedione. It is a weak inhibitor of topoisomerase II. Pixantrone directly alkylates DNA forming stable DNA adducts and cross-strand breaks. Pixuvri is approved for the treatment of adult patients with multiply relapsed or refractory aggressive Non-Hodgkin lymphomas. It is used for patients whose cancer does not respond or has returned after they have received other chemotherapy treatments. The most frequent AE were seen in the blood (mainly neutropaenia), gastrointestinal (nausea, abdominal pain, constipation) and respiratory systems (cough, dyspnea). No drug-drug interaction studies have been submitted and no drug interactions have been reported in human subjects

Pirmenol is an antiarrhythmic agent, which exhibits effects on the fast action potential similar to other class 1 membrane active antiarrhythmic agents. Pirmenol depresses not only the fast Na+ channel, but also others, such as the slow Ca2+ and K+ channels. Pirmenol had sevenfold lower affinity for glandular-type muscarinic receptors (M3) than for cardiac-type muscarinic receptors (M2). This medicine regulates disturbed pulse by acting on the cardiac muscle. Usually, used for treatment of tachyarrhythmia (ventricular). The most commonly reported adverse reactions include constipation, discomfort in stomach, difficulty in urination (urinary retention), headache, insomnia, bitterness in the mouth, nausea, dry mouth and palpitation. Lidocaine, procainamide and quinidine a greater degree of arrhythmia conversion occurred when dosed 15 min after pirmenol than when these agents were dosed alone.

Melperone is an antipsychotic drug which is used in Europe for the treatment of sleep disorders, agitation and confusion states. The exact mechanism of melperone action is unknown.

Pipotiazine (Piportil), also known as Pipothiazine, is a typical antipsychotic of the phenothiazine class used in the United Kingdom and other countries for the treatment of schizophrenia. Its properties are similar to those of chlorpromazine. Piportil® L4 (pipotiazine palmitate) is the palmitic ester of pipotiazine, a piperidine phenothiazine with antipsychotic properties and weak sedative activity. The esterification of pipotiazine is responsible for its prolonged duration of action. The onset of action appears usually within the first 2 to 3 days after injection and the effects of the drug on psychotic symptoms are significant within one week. Improvement in symptomatology lasts from 3 to 6 weeks, but adequate control may frequently be maintained with one injection every 4 weeks. However, in view of the variations in individual response, careful supervision is required throughout treatment. Piportil L4 has actions similar to those of other phenothiazines. Among the different phenothiazine derivatives, Piportil L4 appears to be less sedating and to have a weak propensity for causing hypotension or potentiating the effects of CNS depressants and anesthetics. However, it produces a high incidence of extrapyramidal reactions.

Josamycin is a macrolide antibiotic produced by Streptomyces narbonensis var. josamyceticus. Macrolides are inhibitors of protein synthesis. They impair the elongation cycle of the peptidyl chain by specifically binding to the 50S subunit of the ribosome. Josamycin has antimicrobial activity against a wide spectrum of pathogens. It is similar to erythromycin, but does not induce macrolide resistance in staphylococci and appears to have a lower incidence of gastrointestinal side effects. Josamycin is under investigation in US.

Piroheptine is an antagonist of muscarinic acetylcholine receptors. The drug was used for the treatment of Parkinson's disease, however, it is no longer marketed.

Benserazide is a peripherally-acting aromatic L-amino acid decarboxylase (AADC) or DOPA decarboxylase inhibitor. Benserazide is only used in conjunction with L-dopa for the treatment of Parkinson's disease under the brand name Madopar in the UK. Madopar HBS (125 mg) is a controlled-release dosage form with 100 mg L-dopa and 25 mg benserazide.

Pirenzepine is a M1 muscarinic receptor antagonist, which is prescribed for the treatment of gastric and duodenal ulcer in Europe. The drug preferentially acts on the gastric mucosa to inhibit secretion of both gastric acid and pepsin. Experiment with healthy volunteers demonstrated that pirenzepine passes the blood-brain barrier, but only to a small extent.

Propionylpromazine is used as a neuroleptic to combat stress in pets and farm animals. The main use is to combat stress in the transport of pigs. Propionylpromazine was in common use in veterinary practice in the 1950s and 1960s. Propionylpromazine is of interest to JECFA because of the illicit use at pharmacological dosage (< 1 mg/kg i.m.) in the immediate pre-slaughter period.

Unithiol was developed in the Soviet Union in the late 1950s. It only became more widely used in America and Western Europe since the mid-1970s, and particularly since the late 1970s when the Heyl Company in Germany began production. It remained the mainstay of chelation treatment of arsenic and mercury intoxication for more than half a century. Unithiol has been used in the management of acute and chronic poisoning with a number of different metals and metalloids, and is particularly useful for arsenic, bismuth and mercury. Unithiol can be given parenterally or orally depending on the clinical situation and severity of poisoning. Its action mechanism is close that of complexones. Active sulfhydryl groups enter into reactions with thiol poisons present in blood and tissues, form not toxic complex with them eliminated with urine. The poisons fixation results in the body enzyme systems changed under the poisons effect functions restoration. It is efficient as an antidote in case of intoxications by arsenic and heavy metals salts.