The variety of drugs that have been tried by those seeking “new experiences” (highs, lows, “out-of-body experiences”) defies belief. These drugs include various stimulants, depressants, analgesics, and hallucinogens. Among these are PCP (1-(1-phenylcyclohexyl) piperidine), or phencyclidine, and ketamine (related anesthetic agents); lysergic acid diethylamide (LSD), the most potent hallucinogen known; “ecstasy” (3,4-methylenedioxymethamphetamine [MDMA]); and “bath salts”, synthetic cathinones that are chemically related to khat, a widely used stimulant in East Africa. Not much is known about the long-term deleterious effects of any of these agents. Acutely, LSD has unpredictable effects on mood, affect, and thought, sometimes leading to bizarre and dangerous behaviors. Chronic use of ecstasy may deplete the CNS of serotonin, potentially leading to sleep disorders, depression, anxiety, and aggressive behavior.
Therapeuticdrugs(ADRs)ornontherapeuticagents(drugabuse)mightcausedruginjury.
Anti-neoplasticagents,long-actingtetracyclines,andotherantibiotics,HRTpreparationsandOCs,acetaminophen,andaspirinarethedrugsmostfrequentlyinvolved.
HRTincreasestheriskofendometrialandbreastcancersandthromboembolismbutdoesnotappeartoprotectagainstischemicheartdisease.OCshaveaprotectiveeffectagainstendometrialandovariancancersbutincreasetheriskofthromboembolismandhepaticadenomas.
Overdoseofacetaminophenmaycausecentrilobularlivernecrosis,leadingtoliverfailure.EarlytreatmentwithagentsthatrestoreGSHlevelsmaylimittoxicity.AspirinblockstheproductionofthromboxaneA2,whichmayproducegastriculcerationandbleeding.
Thecommondrugsofabuseincludesedative-hypnotics(barbiturates,ethanol),psychomotorstimulants(cocaine,amphetamine,ecstasy),opioidnarcotics(heroin,methadone,oxycodone),hallucinogens(LSD,mescaline),andcannabinoids(marijuana,hashish).Theyhavediverseeffectsonvariousorgans.
Injury induced by physical agents is divided into the following categories: mechanical trauma, thermal injury, electrical injury, and injury produced by ionizing radiation. Each type is considered separately.
Mechanical forces may inflict a variety of forms of damage. The type of injury depends on the shape of the colliding object, the amount of energy discharged at impact, and the tissues or organs that bear the impact. Bone and head injuries result in unique damage and are discussed elsewhere (Chapter 23). All soft tissues react similarly to mechanical forces, and the patterns of injury can be divided into abrasions, contusions, lacerations, incised wounds, and puncture wounds (
Fig. 8.13