Zakhireye Khwarazmshahi is a Persian

Persian language

Persian is an Iranian language within the Indo-Iranian branch of the Indo-European languages. It is primarily spoken in Iran, Afghanistan, Tajikistan and countries which historically came under Persian influence...

 medical encyclopedia written by the Persian

Persian people

The Persian people are part of the Iranian peoples who speak the modern Persian language and closely akin Iranian dialects and languages. The origin of the ethnic Iranian/Persian peoples are traced to the Ancient Iranian peoples, who were part of the ancient Indo-Iranians and themselves part of...

 scholar Ismail Gorgani

Ismail Gorgani

Ismail Gorgani , with the full name of Sayyid Zayn al-Din Isma'il al-Husayni al-Jurjani , was one of the most famous Persian physicians in Iranian and Islamic traditional medicine...

 (1040-1136). It was composed between 1111 AD and 1136.

Organization

The Zakhira Khwarizmshahi was heavily influenced by the Canon (Qanun)

The Canon of Medicine

The Canon of Medicine is an encyclopedia of Galenic medicine in five books compiled by Ibn Sīnā and completed in 1025. It presents a clear and organized summary of all the medical knowledge of the time...

 of Avicenna

Avicenna

Abū ʿAlī al-Ḥusayn ibn ʿAbd Allāh ibn Sīnā , commonly known as Ibn Sīnā or by his Latinized name Avicenna, was a Persian polymath, who wrote almost 450 treatises on a wide range of subjects, of which around 240 have survived...

 and was modeled after that work.

The Encyclopedia consists of 10 volumes and is one the earliest Encyclopedias to be written in Persian. The Persian text of this large Encyclopedia was edited and published by Saidi Sirjani in 1976. The book illustrates traditional medicine that was used in the Islamic world for variety of pains and diseases.

For example, on "Drugs recommended for lice control," Gorgani recommends the following method:
Most of the above botanicals have recently been shown to possess insecticidal properties.