Toxicity associated with long-term intravenous heroin and cocaine self-administration in the rat.
Level 5 - mechanism / opinion, no new human data
Animal research with no human data
What was done
Laboratory rats were given continuous, unlimited access to self-administer either intravenous cocaine hydrochloride or intravenous heroin hydrochloride for up to 30 days. Investigators observed drug intake patterns, grooming behavior, body weight changes, general physical condition, and 30-day mortality rates.
What was found
Rats self-administering cocaine developed an episodic intake pattern, ceased grooming, lost up to 47% of pretesting body weight, showed pronounced physical deterioration, and had a 90% mortality rate at 30 days. Rats self-administering heroin maintained stable intake (with gradual increases over the first two weeks), preserved grooming and baseline body weight, and had a 36% mortality rate over 30 days.
Why it matters
This study provides controlled laboratory evidence that continuous, unrestricted access to cocaine produces substantially faster physiological deterioration and higher mortality than unlimited access to heroin.
Limits
This is an animal study, and findings may not directly translate to human substance use, which involves variable dosing patterns, adulterants, and social factors. The abstract does not report the total sample size (n), exact dosage amounts, or formal statistical significance testing.
Cited by
- supports Laboratory rodents provided with self-administered cocaine will repeatedly press a lever for the drug until reaching exhaustion or death.