For sites that offer brief factual information, such as lists of effects and risks.
For sites about, or related to, medical use of the drug.
For sites about, or related to, ketamine's use in inducing near death experiences.
For news articles and press releases about ketamine.
For sites detailing personal experiences of ketamine use, including reports of the effects.
For sites about, or detailing, research into ketamine, its effects, or its potential uses.
For sites about, or related to, veterinary use of the drug.