Dictionary

Pharmacology

Drugs, drug classes and the words used to give medications safely.

half-lifeThe time it takes for the amount of a drug in the body to fall by half.

haloperidolA first-generation antipsychotic drug, given by mouth or injection, used for psychosis and severe agitation.

HCT (hydrocortisone)HCT written for the drug hydrocortisone: an abbreviation ISMP lists as error-prone. It is not the lab value Hct (hematocrit).

HCTZAn abbreviation for hydrochlorothiazide, a thiazide diuretic; it should not be used because it can be misread.

heavy metalA dense metal, such as lead, mercury or arsenic, that can poison the body even in small amounts.

heparinAn anticoagulant drug, given by injection or IV, that keeps blood clots from forming or growing.

hepatitis B immune globulinA shot of ready-made antibodies against the hepatitis B virus, giving short-term protection right away.

hepatitis B vaccineA vaccine that protects against hepatitis B, a virus that infects the liver.

herbalMade from plants; herbal supplements are plant products taken for health, sold without a prescription.

high-alert medicationA drug that can cause serious harm to a client if it is used in error; also called a high-risk medication.

histamineA chemical released by certain immune cells that widens blood vessels, makes them leaky and tightens airway muscles.

HITHeparin-induced thrombocytopenia: an immune reaction to heparin that lowers the platelet count.

HMG-CoA3-hydroxy-3-methylglutaryl coenzyme A: a substance the liver uses on its way to making cholesterol.

hormonal contraceptiveA birth control method that uses hormones to prevent pregnancy.

hormone replacement therapyTreatment with hormones, usually estrogen with or without a progestin, to replace hormones the body no longer makes enough of.

HSAn abbreviation that has been used for "at bedtime" (from Latin hora somni) and for "half-strength".

hydralazineA vasodilator that lowers blood pressure by relaxing the walls of the arteries.

hydrochlorothiazideA thiazide diuretic that lowers blood pressure and reduces swelling by helping the kidneys remove salt and water.

hydrocodoneAn opioid pain medicine taken by mouth, often combined with acetaminophen in one tablet.

hydrocortisoneA corticosteroid drug that is the same as the body's own cortisol, given by mouth, IV, on the skin or rectally.

hydrogen peroxideA clear liquid antiseptic that bubbles as it releases oxygen, used diluted to clean and disinfect.

hydromorphoneA strong opioid pain medicine, given by mouth, by injection or into a vein.

hydroxyureaA drug taken by mouth that slows the making of new cells, used for sickle cell disease and some blood cancers.

hydroxyzineA sedating antihistamine used for anxiety, itching and nausea, and to calm clients before or after surgery.

hypersensitivityAn overreaction of the immune system to a substance that is usually harmless.