Intravenous self-administration of propoxyphene napsylate: case report and in-vitro studies

A man who was prescribed propoxyphene napsylate (PN) for treatment of heroin addiction stated that he received no effect from the drug by the oral route. He then decided to administer the drug to himself intravenously in a manner identical to that used by most heroin addicts (heating the tablet with water in a spoon and drawing the liquid through a needle); this procedure brought him immediate subjective relief. Several reports have stated than PN is not efficacious via the intravenous route since it is relatively water insoluble and is therefore not likely to be abuse in this manner. However, in vitro experiments demonstrated that at least 1 mg of PN can be extracted by 10 mL of hot water from a tablet containing 100 mg of the drug. Assuming (as a conservative estimate) that the subject received a bolus injection of approximately 40 mg PN (he used four 100 mg tablets at once), his response may not have been entirely subjective. Moreover, severe cardiovascular and pulmonary complications may ensure as a result of the insoluble material injected.