Concerning the dispute of nitrous oxide filled in cartridges so called “Siva Gas” which is misused like a narcotic drug, Wakayama Prefecture designated it as a product under governor’s observation on August 21 which was the earliest across the country. Since the gas was so designated, it has turned out to be compulsory for those who sell or purchase Siva Gas in the prefecture to register also to the neighboring prefectures. A similar ordinance has also been enacted in Tottori Prefecture, and it seems that the trend will by the other prefectures of the country from now on.

It has been controversial these days that some play to inhale nitrous acid (laughter gas) prevails among those who seek a temporal euphorigenic feeling. The gas named “Siva Gas” filled in a small cartridge sized about 5cm particularly is said to be sold in the form of kit to inhale from the balloon stuffed with a laughter gas actually after unsealing by a puncher, although it is sold over the Internet under the official name of “Air Pressure Adjusting Gas for Bicycle”. It is guessed to be an imported article but details are unknown.

According to the Pharmaceutical Affair Section of Wakayama Prefectural Welfare and Health Department, the prefecture decided to restrict by the ordinance now that it is difficult to restrict the inhalation of nitrous oxide at any legal level while it is actually being used medically for the anesthetic purposes.

Wakayama Prefecture has been implementing generally its own restriction system named “System of Product under Governor’s Observation” since April 2013 which is aimed to avoid any abuse of drugs under the Wakayama Prefectural Ordinance Concerning Abuse of Drugs.

The system has been provided mainly to cope with the dangerous drugs, which is aimed to designate the products sold actually for inhalation purposes despite their suggested usage for “Incense” or “Herb,” and to make mandatory to register their selling and purchasing to the prefectural office. The registration includes the statement that the products will not be used for inhalation and any violation of the ordinance shall be imposed a penalty of 50 thousand yen.

The Pharmaceutical Affair Section of Wakayama Prefecture caught the information of “Siva Gas” in June 2015, and started a deliberation just for avoiding purposes although there has been no incident relating to the said gas in the prefecture.


After 2 months of deliberations in the pharmaceutical examination and deliberation committee, the proposal was approved the governor and then the “Siva Gas” was designated as a product under the governor’s observation on August 21. According to the Pharmaceutical Affair Section of Wakayama Prefecture, there has appeared a certain effect that part of the Internet shop of Siva Gas stopped selling to Wakayama Prefecture.

On the other hand, however, even a little change of the name will not be applicable to the restriction because the brand and appearance of Siva Gas is under the restriction. Therefore, some similar products are seen under a different name and from time to time they will be added to the items under the observation.

For information there is a similar case of restriction at an ordinance level. On August 28, Tottori Prefecture added “Siva Gas” to the list of governor’s designated pharmaceutical candidates based on the Prefectural Abuse-preventing Ordinance of Pharmaceuticals. The similar case of restriction will be expanded throughout Japan.