drug resistance

resistance /re·sis·tance/ (re-zis´tans)

1. opposition, or counteracting force.

2. the natural ability of an organism to resist microorganisms or toxins produced in disease.

3. the opposition to the flow of electrical current between two points of a circuit. Symbol R or .

4. in psychiatry, conscious or unconscious defenses that prevent material in the unconscious from coming into awareness.

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airway resistance  the opposition of the tracheobronchial tree to air flow. Symbols RA, RAW.

androgen resistance  resistance of target organs to the action of androgens; the result is any of a spectrum of defects. In mild to incomplete types the person may have a definite male phenotype but infertility, or may have ambiguous genitalia. In the complete type the person has a female phenotype but XY chromosomes.

drug resistance  the ability of a microorganism to withstand the effects of a drug that are lethal to most members of its species.

electrical resistance  resistance (3).

multidrug resistance , multiple drug resistance in some malignant cell lines, resistance to many structurally unrelated chemotherapy agents in cells that have developed natural resistance to a single cytotoxic compound.

vascular resistance  the opposition to blood flow in a vascular bed.

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drug resistance,

the ability of disease organisms to resist effects of drugs that previously were toxic to them. Bacterial resistance to an antibiotic can result from mutation of a strain that has been exposed to an antibiotic or similar agent. Such acquired resistance may result from a chromosomal disruption or acquisition of a stray bit of deoxyribonucleic acid (DNA) on a resistant plasmid. It can also be caused by extrachromosomal pieces of DNA that carry codes for antibiotic-resistant genes from a transposon, a DNA segment capable of insertion into a bacterial chromosome-resistant plasmid, or both. Decreased permeability to an antimicrobial is a common form of intrinsic resistance. Alteration or inactivation of the antibiotic is perhaps the most common mechanism of drug resistance. Acquired resistance to beta-lactam antibiotics is determined by the production of enzymes that inactivate the antibiotic. Drug resistance may also result from a change in the target site on which it acts.

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drug(s),

n a substance used in the prevention, cure, or alleviation of disease or pain or as an aid in some diagnostic procedures.

drug absorption,

n See absorption, drug.

drug abuse,

n an excessive or improper use of drugs, especially through self-administration for nonmedical purposes. This term has increased significance because of the enactment of the Comprehensive Drug Abuse Prevention and Control Act of 1970, which replaces the Harrison Narcotic Act. See also substance abuse.

drug combinations,

n.pl the use of drugs together to enhance the properties of both to the benefit of the patient.

drug dependence,

n a physical or psychologic state in which a person displays withdrawal symptoms if drug use is halted suddenly; can lead to addiction.

Drug Enforcement Administration (DEA),

n.pr the federal agency charged with monitoring use and abuse of narcotics. It provides the drug schedules used to determine the addiction potential of dental drugs.

drug hypersensitivity,

n an allergic reaction that occurs after exposure to a suspect medication. It may manifest with a fever or rash and in severe cases, organ damage or death. It is classified as (1) immediate or occurring rapidly after exposure, or (2) delayed or occurring several days after exposure.

drug idiosyncrasy

n an adverse drug reaction that occurs in a small number of persons and presents no correlation to dosage or means of therapy.

drug interaction,

n a modification of the effect of a drug when administered with another drug. The effect may be an increase or a decrease in the action of either substance, or it may be an adverse effect that is not normally associated with either drug.

drug resistance,

n the capacity of a microorganism to build a tolerance to a drug.

drug stability,

n the length of time a drug retains its properties without loss of potency; usually referred to as shelf life.

drug therapy,

n the use of a drug in the treatment of a patient with a specific disease or illness.

drug tolerance,

n the body's ability to increasingly withstand the effects of the substance being used, thereby requiring larger quantities of said substance in order to bring about the desired result.

drug toxicity,

n the critical or lethal reaction to an erroneous dosage of a medication. Drug toxicity may occur due to human error or intentional overdose in the case of suicide or homicide.

drugs, antibiotic,

n.pl the chemical compounds obtained from certain living cells of lower plant forms, such as bacteria, yeasts, and molds, and from synthesis. They are antagonistic to certain pathogenic organisms and have a lethal effect on them.

drugs, antimicrobial,

n.pl the drugs, mainly penicillin and its derivatives, used to combat viral, fungal, and parasitic infections.

drugs, antiseptic,

n.pl the chemical compounds used to reduce the number of microorganisms in the oral cavity.

drugs, autonomic,

n.pl the drugs that mimic or block the effects of stimulation of the autonomic nervous system.

drugs, desensitizing,

n.pl the agents used to diminish or eliminate sensitivity of teeth, especially the dentin, to physical, chemical, thermal, or other irritants (e.g., strontium chloride, silver ammoniacal] or potassium nitrate, sodium fluoride, formalin, zinc chloride). See hypersensitivity, dentin.

drugs, endodontic,

n.pl the drugs used in treating the dental pulp and dental periapical tissues.

drugs, nonofficial,

n.pl the drugs that are not listed in the United States Pharmacopeia (U.S.P.) or the National Formulary (N.F.).

drugs, official,

n.pl the drugs listed in the U.S.P. or N.F.

drugs, officinal

n.pl drugs that may be purchased without a prescription. More commonly called
over-the-counter (OTC) drugs.

drugs, over-the-counter (OTC),

n.pl the drugs that may be purchased without a prescription. Sometimes called nonlegend drugs because the label does not bear the prescription legend required on all drugs that may be dispensed only on prescription.

drugs, parasympathetic

n.pl the belladonna alkaloids that inhibit glandular secretions of the nose, oral cavity, pharynx, and bronchi. This is the main reason for using atropine and scopolamine for preanesthetic or preprocedural medication.

drugs, parasympatholytic

(per´sim´pthōlit´ik),
n.pl the drugs that block nerve impulses passing from parasympathetic nerve fibers to postganglionic neuroeffectors.

drugs, parasympathomimetic

(per´sim´pthōmimet´ik),
n.pl the drugs that have an effect similar to that produced when the parasympathetic nerves are stimulated.

drugs, proprietary

(prprī´iter´ē),
n.pl the drugs that are patented or controlled by a private organization or manufacturer.

drugs, psychoactive

n.pl the drugs or other agents that have the capacity to become habit forming because of their influence on mood, behavior, or conscious thought; may be therapeutic or recreational.

drugs, sympathetic,

n.pl the agents that imitate the sympathetic autonomic nervous system actions. They usually cause raised levels of alertness and anxiety. Various types are used in dentistry as vasoconstricters in conjunction with local anesthetics. See also adrenergic agents.

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drug

1. any medicinal substance.

2. a narcotic.

3. to administer a drug.

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drug administration

includes aerosol, oral, transtracheal infusion, subcutaneous, intramuscular, intravenous, intrauterine, intraperitoneal, intra-articular, intramammary, intrathecal, subconjunctival, percutaneous, percutaneous intraruminal, gas inhalation. Mass medication is per feed or drinking water or, in the case of captive fish, in the tank water. For feral animals individual dosing by projectile dart is usual, for group therapy administration by bait is possible.

drug allergy

immune-mediated hypersensitivity to a drug molecule. Includes anaphylaxis, cutaneous reaction.

animal drug

a drug specifically tested for, and recommended for use in, animals. A legal point of importance if an animal dies as a result of an unusual or allergic reaction to medication with a drug not licensed for use in animals.

drug augmented swine dysentery

pigs receiving prophylactic medication are more severely affected than untreated pigs.

bactericidal/bacteriostatic drug

see antibiotic.

drug binding

binding of a drug to a large molecule in the tissues or fluids, e.g. binding to protein in the blood, may affect the metabolism of the drug, especially its rate of excretion.

chemotherapeutic drug

see chemotherapy.

drug combinations

a pharmaceutical strategy of combining several drugs into one formulation to provide for a specific requirement, e.g. an antibiotic combined with an anti-inflammatory agent in a mastitis ointment. Has the disadvantage that the dose of one drug is determined by the dose of the other.

controlled drug

availability and use of the drug is controlled by law. The control is at various levels of severity depending on the degree of danger associated with the uncontrolled use of each drug.

drug delayed swine dysentery

swine dysentery appears several days after treatment is discontinued.

drug delayed-augmented swine dysentery

after successful treatment during an attack of swine dysentery a more severe form of the disease occurs after treatment ceases.

drug diminished swine dysentery

the disease is reduced in severity as a result of treatment but is not eliminated.

drug eruption

an eruption or solitary skin lesion caused by a drug. See also dermatitis medicamentosa.

drug hypersensitivity

see drug allergy (above).

mutagenic d's

those that affect the DNA of the target organism have the hazard of creating new races of microorganisms with increased pathogenicity.

drug residue

the amount of the drug that can be detected in tissues at specified times after administration of the drug ceases. See also drug tolerance (below).

drug resistance

said mainly of antibacterial drugs and of microorganisms that are unaffected by the drug whilst most organisms of its species are susceptible. The resistance may be inherent or secondary to frequent exposure at sublethal levels. Resistance of an animal to a specific drug, e.g. to insulin, can also occur in this way.

drug resistant swine dysentery

medication of the feed is not an effective procedure and diarrhea and deaths occur.

drug safety margin

the magnitude of the difference between the dose required to produce a maximum therapeutic effect and that which produces a toxic effect. Registering authorities require this information.

drug selectivity

capacity to produce a single effect.

teratogenic drug

produces a toxic effect on the fetus at a particular phase of development producing a malformation.

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resistance

1. opposition, or counteracting force, as opposition of a conductor to passage of electricity or other energy or substance.

2. the natural ability of a normal organism to remain unaffected by noxious agents in its environment. See also immunity.

3. acquired ability of a bacterium or helminth or arthropod parasite to survive in the presence of concentrations of a chemical which are normally lethal to the organisms of that species. Occurs usually as a result of prolonged growth of the organism in sublethal concentrations of the agent and the survival of the organisms which have the least innate susceptibility to the agent. Has serious implications for animals which may find themselves without a suitable remedy for a disease, and for humans who may experience transfer of a resistant organism from the food supply.

4. in studies of respiration, an expression of the opposition to flow of air produced by the tissues of the air passages, in terms of pressure per amount of air per unit of time.

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drug resistance

the ability of a microorganism to withstand doses of a drug that are lethal to most members of its species.

peripheral resistance

resistance to the passage of blood through the small blood vessels, especially the arterioles.

transferable resistance

antimicrobial resistance genes carried by bacteria on plasmids or transposons can often be readily acquired by other strains of the same species, by different species, and sometimes by organisms in different genera. Of considerable import in consideration of the implications of antimicrobial therapy in animal populations and in public health. The full significance is difficult to ascertain.

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drug resistance

The ability of bacteria and other microorganisms to withstand a drug to which they were once sensitive