2000 Years of Natural Products Research 

Past, Present and Future 

July 26-30, 1999
Amsterdam, The Netherlands

American Society of Pharmacognosy

Gesellschaft für Arzneipflanzenforschung

Association Française pour l'enseignement
et la Recherche en Pharmacognosie

Chemical-Pharmaceutical Characterisation of MGM (Medical Grade Marihuana), a product of Maripharm

H. F. Bos, W.G. van der Sluis
Division of Pharmacognosy, Faculty of Pharmacy, Universiteit Utrecht, Sorbonnelaan 16, 3508 TB Utrecht, The Netherlands.

In the past few years there has been a growing interest in the use of marihuana for medical purposes, e.g. treatment of nausea and vomiting in oncolytic therapy, multiple sclerosis, glaucoma and anorexia associated with AIDS [1].
This has led to the introduction of Medical Grade Marihuana. A high level of product uniformity is reached by cloning a variety of Cannabis sativa L., and keeping growth conditions almost the same. These include nutrients and breeding soil constitution, temperature, air-humidity, duration and intensity of lighting and harvest time. After harvesting, the flowering tops are dried and packaged in airtight containers, protected from light and humidity. The packaged marihuana is sterilised by gammairradiation (performed by Gammaster BV).
The cannabinoids determining the quality are &Mac198;9-tetrahydrocannabinol (THC) and its 2-carboxylic acid (THCA). The amount of THCA exeeds the amount of the other cannabinoids by far. THC is the major pharmacologically active substance, to which THCA is easily converted by decarboxylation, e.g. during heating. Cannabinol (CBN) is the non-active decomposition product of THC.
Validated are: the sampling, the extracting method, TLC, HPLC and GC-MS. HPLC was the method of choice for quantitative analysis of cannabinoids.
An investigation to the stability was performed on samples of one charge at three different temperatures: 2-8 degreesC, room temperature (15-25degreesC) and 35-45degreesC.
After storage for one year at room temperature not more than 4% of the THC (calculated as total THCA + THC) was decomposited in CBN; at 2-8degreesC, decomposition was even less. At 35-45degreesC, the decomposition was already more than 50% after six months.
The following specifications are proposed:
On delivery: the product contains not less than 10.0 % w/w THC (calculated as the total amount of THCA + THC) and not more than 0.1 % w/w CBN.
End-of-shelf-life: the product contains not less than 9.0 % w/w THC (calculated as total THCA + THC) and not more than 1.0 % w/w CBN.
The product can be kept for two years at room temperature (15-25degreesC).
Further analytical specifications such as limits on the microbiological contamination, organochloro- and organophosphorous pesticides proved to be well in range of the usual demands on vegetable drugs [2].

1. Cannabis, the scientific and medical evidence. London:The stationery office, 1998
2. Ph. Eur. - proposed general monograph on vegetable drugs, 1995.
"Stichting KNMP-fondsen" is acknowledged for sponsoring.

Phytochemical Society of Europe