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Dictionary

Pharmacology

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

ondansetronA drug that prevents and treats nausea and vomiting.
onsetThe beginning of something, such as when a symptom started or how soon a drug starts to work after it is given.
ophthalmicHaving to do with the eye, or describing a medicine made to be put in the eye.
opioid analgesicA strong drug that relieves moderate to severe pain by acting on the brain and spinal cord.
opioid antagonistA drug that blocks opioid receptors, stopping or reversing the effects of opioids.
oralRelating to the mouth, or taken by mouth.
oral syringeA needleless syringe used to measure and give liquid medicine by mouth.
orallyBy mouth.
OSAn abbreviation for left eye, from the Latin oculus sinister.
oseltamivirAn oral antiviral drug used to treat and prevent influenza.
osmoticRelating to osmosis, the movement of water across a membrane toward the side with more dissolved particles.
OUAn old abbreviation for "both eyes" that should not be used; write "each eye" or "both eyes" instead.
over-the-counterSold without a prescription.
over-the-counter medicationA medicine that can be bought without a prescription.
overdoseTaking more of a drug or substance than the body can safely handle, whether by accident or on purpose.
oversedationA level of drowsiness deeper than intended from opioids or other sedating drugs.
OXYAn abbreviation for oxytocin; ISMP advises writing the full drug name.
oxybutyninAn anticholinergic drug that relaxes the bladder muscle, used for overactive bladder.
oxycodoneAn opioid pain medicine taken by mouth, as quick-acting or long-acting tablets.
oxygenA gas in the air that every cell needs, also given as a medicine at higher amounts than room air.
oxytocinA hormone that makes the uterus contract and releases breast milk; also given by IV to start or strengthen labor and control bleeding after birth.
paclitaxelA chemotherapy drug, given by IV, that stops cancer cells from dividing.
paliperidoneA second-generation antipsychotic drug, taken as a daily tablet or given as a long-acting injection.
pantoprazoleA proton pump inhibitor, taken by mouth or IV, that strongly lowers the amount of acid the stomach makes.
parasympathetic nervous systemThe part of the autonomic nervous system that calms the body, slows the heart and helps digestion during rest.
parenteralGiven by a route other than the digestive tract, usually by injection or into a vein.
paroxetineAn SSRI antidepressant used for depression and several anxiety disorders.
patient-controlled analgesiaA way of giving pain medicine in which the client presses a button to give themselves a set dose from a programmed pump.
peak and trough levelsBlood tests of a drug's highest level after a dose (peak) and its lowest level just before the next dose (trough).
PEGAn abbreviation that can mean a feeding tube placed through the belly into the stomach, or the laxative polyethylene glycol.
penicillamineAn oral drug that binds copper and some other metals so they leave the body in the urine.
penicillin G benzathineA long-acting form of penicillin given as a deep muscle injection that releases the drug slowly over weeks.
penicillinsA group of antibiotics, including penicillin and amoxicillin, that kill bacteria by stopping them from building their cell walls.
per osLatin for "by mouth"; a way of writing the oral route that should not be used.
permethrinA cream or lotion put on the skin or hair to kill lice and the mites that cause scabies.
perphenazineA first-generation antipsychotic drug of the phenothiazine group, used for schizophrenia and for severe nausea and vomiting.
pharmacistA licensed health professional who prepares and dispenses medicines and advises on their safe use.
pharmacodynamicsThe study of what a drug does to the body, and how it does it.
pharmacokineticsHow the body takes in, spreads, changes and gets rid of a drug over time.
pharmacologyThe study of drugs: what they are, how they work in the body and how the body handles them.
pharmacyA place where medicines are prepared and given out, or the profession of preparing and dispensing them.
phenazopyridineA drug that numbs the lining of the urinary tract to ease burning, urgency and pain with urination.
phenelzineA monoamine oxidase inhibitor (MAOI) antidepressant taken by mouth.
phenobarbitalA long-acting barbiturate used to control seizures, including seizures in newborns.
phentermineA stimulant-like drug that lowers appetite, used for a short time to help with weight loss.
phenylephrineA drug that tightens blood vessels, given IV to raise low blood pressure and used in nose sprays and eye drops.
phenytoinAn anticonvulsant drug, given by mouth or IV, used to prevent and stop seizures.
phenytoin levelA blood test that measures how much of the antiseizure drug phenytoin is in the blood.
phytonadioneVitamin K1 given as a drug, by mouth or injection, to help the blood clot.
pilocarpineA cholinergic drug used as eye drops to lower pressure in the eye, and by mouth to treat dry mouth.