6. Outlook

After it had been demonstrated that test systems containing some alkaloids or alkaloid N-oxides exhibited an antitumor effect several attempts were made to use PAs in medicinal treatment of carcinosis [391-393]. Since indicine itself does not show mutagenic properties its N-oxide (28) was successfully applied in clinical studies on infantile leukemia. Unfortunately, liver damages like liver necrosis and liver cirrhosis were observed as side reactions so that a further therapeutic utilization was no longer justified [394-404].

In the Pharmacopoea Sinica of 1978 the alkaloid monocrotaline is described. It was used for the treatment of dermatomas. On account of its highly toxic and carcinogenic side effects it is not mentioned in the new edition of 1985 and also no longer used.

The saturated alkaloid platyphylline (48) displays spasmolytic and antiasthmatic properties and was included in the Pharmacopoe of the former UDSSR <Soviet Union> (1980). Compared to other spasmolytics and antiasthmatics it exhibits no particular effect so that it has gained no importance.

The use of medicinal plants represents a considerable risk of health. Because of the liberalization of the international world trade an increasing number of medicinal plants are offered as "miracle drugs" and imported to Europe without control as the example of the Emilia herb demonstrates [152, 153]. The medicinal plants of the genera resp. the species of the latter compiled in Table 1 should not be used on any account because they contain toxic PAs which may cause damage to health.

Medicinal plants in Europe containing pyrrolizidine alkaloids was written by Prof. Dr. E. Röder and published in the journal "Pharmazie" 50 (1995), pages 83-98.