In Finnish data from 1995-2000, 1006 fatal
poisonings due to alcohol (
ethanol), a single
drug or both were statistically analysed in retrospect to evaluate the interaction between alcohol and drugs. In 53% of these cases, low concentrations of some common
benzodiazepines were present. The median postmortem
blood alcohol concentration (BAC) was 3.3 percent per thousand (w/w) in the 615 alcohol
poisonings, but significantly lower, ranging from 1.3 to 1.7 percent per thousand, when
promazine,
doxepin,
amitriptyline or
propoxyphene were found together with alcohol. When
levomepromazine,
temazepam or
zopiclone were present, the median BAC was also significantly lower, 2.5-2.7 percent per thousand.
Citalopram and
diltiazem did not exhibit a significant effect. The median BAC was significantly lower in cases with high concentrations than in those with low concentrations of a
drug (excluding
citalopram), suggesting a positive concentration-effect relationship. Fatal toxicity indices (FTIs) were calculated by relating the number of deaths caused by a
drug to the corresponding sales figures.
Promazine had an extremely high FTI, followed by
levomepromazine,
propoxyphene,
doxepin and
amitriptyline. The other drugs had relatively low FTIs. The results reflect not only the acute toxicity of a given
drug-alcohol combination but also the manners of use and abuse of these drugs.