Microscopic Examination of Herbal Drugs

A revised version of the European Pharmacopoeia (Ph. Eur.) chapter 2.8.23. Microscopic examination of herbal drugs has been published in Pharmeuropa 37.4. The public comment deadline is 31 December 2025.

Key Updates

The chapter has been updated to allow for more flexibility in the particle size. Microscopic examination of herbal drugs is carried out on the powdered herbal drug of an appropriate degree of fineness, usually determined by sieving. The sieve number specified in an individual monograph is an example of a sieve that is suitable for the herbal drug described. Where the herbal drug is sieved but the sieve number is not indicated in the individual monograph, sieve number 355 (see Ph. Eur. chapter 2.1.4) is most suitable.

Sieves are defined in the general Ph. Eur. chapter 2.1.4. Sieves and instructions for their use are given in the general Ph. Eur. chapter 2.9.12. Sieve test. For the purpose of microscopic examination of herbal drugs, the powder can be used once it has been passed through a single sieve.

For more information please go to Pharmeuropa online.