Drugs for Final Flashcards
Methyldopa
Can initiate an autoimmune reaction
Blood pressure medication that is an alpha receptor drug and is used to tx HTN.
Causes hemolytic anemia-destruction of the RBC.
Monitor H&H and CBC
Hydralazine
Can initiate an autoimmune reaction
Lupus like syndrome
Notify and follow up
Isoniazid
Can initiate an autoimmune reaction
Lupus like syndrome
Notify and follow up
Procainamide
Can initiate an autoimmune reaction
Lupus like syndrome
Notify and follow up
Barbituates
Can cause a skin rash stevens-johnson in toxicity
Sulfonamides
Can cause a skin rash stevens-johnson in toxicity
Phenytoin
Can cause a skin rash stevens-johnson in toxicity
Carbamazepine
Can cause a skin rash stevens-johnson in toxicity
Allopurinal
Can cause a skin rash stevens-johnson in toxicity
NSAIDs
Can cause a skin rash stevens-johnson in toxicity
Penicillins
Can cause a skin rash stevens-johnson in toxicity
Gentamicin
Progressive renal failure- renal tubular injury reversible upon cessation
Amphotericin B
Progressive renal failure- high frequency of injury because mechanism for efficacy is shared by the mechanism responsible for toxicity
Contrast-Media
Progressive renal failure- dose related nephrotoxicity
Doxorubicin
Cardiovascular toxicity
Leads to production of reactive oxygen species
Bleomycin
Can result in pulmonary toxicity by pulmonary fibrosis
Amiodarone
Can result in pulmonary toxicity by pulmonary fibrosis
Vancomycin
Causes red-man syndrome
Flushing, pruritis, chest pain, muscle spasm, and hypotension during vancomycin infusion.
Pretreatment w/ IV antihistamines attenuates the sx of red-man syndrome.
Cromolyn
Blocks the release of histamine from mast cells.
Inhaled as a powder.
Stabalized mast cells preventing noncytolytic degranulation.
Decreases sx of allergic rhinitis
Prophylactic use to block asthmatic rxns but not useful in managing acute asthmatic attacks.
Poorly absorbed- with few adverse effects (irritation/taste)
Effective only if used BEFORE a challenge
Nedocromil
Blocks the release of histamine from mast cells.
Inhaled as a powder.
Stabalized mast cells preventing noncytolytic degranulation.
Decreases sx of allergic rhinitis
Prophylactic use to block asthmatic rxns but not useful in managing acute asthmatic attacks.
Poorly absorbed- with few adverse effects (irritation/taste)
Effective only if used BEFORE a challenge
Trirolidine, DIPHENHYDRAMINE (benydryl), PROMETHAZINE, HYDROXYZINE, chlorpheniramine
Histamine H1 receptor blockers
1st generation drugs that are widely used, effective and inexpensive.
Loratadine (claritin OTC), desloratadine (clarinex), azelastine (astelin), cetirizine (Zyrtec OTC), fexofenadine (allegra, OTC)
Less CNS toxicity or side effects compared to first generations since they do not cross the blood brain barrier or are excluded by p-glycoprotein (cause less drowsiness.
H1 blockers- active metabolites of the 2nd generation compounds are used therapeutically
Loratadine (Claritin) to desloratadine (clarinex)
terfenadine (seldane) to fexofenadine (Allegra)
Terfenadine (Seldane)- process
Terfenadine undergoes first-pass metabolism to fexofenadine.
Terfenadine blocks potassium channels in myocardium, which causes a prolonged QT interval and increases the risk of ventricular tachyarrhythmias. (torsades de pointes)
Terfenadine (Seldane)
Active metabolites of the 2nd generation compound that is used therapeutically is fexofenadine (allergra)
Loratadine (Claritin)
Active metabolites of the 2nd generation compound that is used therapeutically is desloratadine (clarinex)
Promethazine
The most effective antihistamine used to treat motion sickness.
Administered 1 hr before the anticipated motion.
Prevention of nausea and vomiting by blockage of dopamine D2 receptors
Phenothiazine class
Promethazine and timeprazine
Blockade of dopamine D2 receptors to prevent nausea and vomiting
Diphenhydramine
OTC tx of hyposomnia
Antimuscarinic actions
Magic Mouthwash
Formulated from prescription
Used to treat oral ulcers, infections, inflammation, pain
Contains diphenhydramine
Syrup of Ipecac
Onset 15-20 minutes
95% vomit in 20 mins, 30% reduction in bioavailability at 1 hour
Side effects- acute- diarrhea, drowsiness, chronic- cardiac arrhythmia’s, neuropathy, muscle weakness.
cathartics
activated charchol
Promote movement of AC bound drug through GI tract, may cause hypovolemia and electrolyte imbalance
Activated Charcol
Absorbant 1gm/kg
Will NOT bind- low molecular weight, charge compounds; cyanide, bromide, potassium, ethanol, methanol, iron, lithium, alkaline corrosives, mineral acids, highly concentrated solutions such as gasoline, kerosene, and ETOH
Efficacy 40% reduced bioavailability at 1 hour
ADR- Vomiting, constipation, aspiration, GI obstruction, charcoal empyema, GI perforation.
Golytely
Used in whole bowel irrigation
Used prior to colonoscopy.
Dimercaprol (BAL)
Chelator used for metal poisonings because they bind to metal
uses for As, Hg, Pb, Cd and toxicities include HTN and tachycardia
Penicillamine
Chelator used for metal poisonings because they bind to metal
uses for Cu, Pb, Hg, As, toxicities include allergic rxns
DSMA (succimer)
Chelator used for metal poisonings because they bind to metal
used for Pb, As, Hg, toxicities include Gas and ABD pain
Edetate calcium disodium (EDTA)
Chelator used for metal poisonings because they bind to metal
used for Pb and toxicities include nephrotoxicity
Deferoxamine
Chelator used for metal poisonings because they bind to metal
used for Fe, toxicities include hypotension, anaphyactoid rxn and ARDS
Crotalidae Antivenin
Antivenins/biologics
rattle snake envenomation
Lactrodectus Antivenin
Antivenins/biologics
black widow spider envenomation
Elapidae Antivenin
Antivenins/biologics
eastern and texas coral snake envenomation
Trivalent botulinum
Antivenins/biologics
botulisms type A, B, and E
Digoxin immune fab
Antivenins/biologics
digoxin and digitoxin
N-acetylcysteine
Pharmacologic Antagonists
poisoning is acetaminophen and mechanism is prevents NAPQI binding at hepatocyte.
Naloxone
Pharmacologic Antagonists
poisoning is opioids and mechanisms is opioid receptor antagonist
Flumazenil
Pharmacologic Antagonists
poisoning is benzodiazepines and mechanism is benzodiazepine receptor antagonist
Atropine
Pharmacologic Antagonists
poisoning is organophosphates and pesticides and mechanism is muscarinic receptor antagonist
Fomepizole
Pharmacologic Antagonists
poisoning is methanol and ethylene glycol and mechanism is blocks metabolite formation.
Defuroxamine
Metal antidote for iron
Deferasirox
Metal antidote for iron
Oral option
Penicillamine
Metal Antidote for copper
Trientine
Metal antidote for copper
Parathion
Pesticide
Organophosphate
Acetylcholinesterase inhibitors producing muscarinic and nicotinic toxicity
Malathion
Pesticide
Organophosphate
Acetylcholinesterase inhibitors producing muscarinic and nicotinic toxicity
Diazinon
Pesticide
Organophosphate
Acetylcholinesterase inhibitors producing muscarinic and nicotinic toxicity
Atropine
Pesticide treatment
Muscarinic antagonist
Pralidoxime
Pesticide treatment
Regenerated ACHE
Classifications of ABX- Agents that inhibit cell wall synthesis
Penicillins Cephalosporins Cycloserine Vancomycin Bacitracin
Classifications of ABX- Agents that act directly on the cell membrane of the microorganism affecting permeability and leading to leakage of intracellular compounds
Detergents
- polymyxin
Classifications of ABX- Agents that interfere with protein synthesis by interaction with bacterial ribosomes
Chloramphenicol Tertracyclines Macrolides Clindamycin Streptogramins Ketolides
Classifications of ABX- Agents that interfere with protein synthesis by blocking initiation
Oxazolidinoses (linezolid)
Classifications of ABX- Agents that interfere with protein synthesis by inhibition of tRNA synthesis
Mupirocin
Classifications of ABX- Agents that interfere with protein synthesis by multiple mechanisms leading to disruption of RNA processing
Aminoglycosides
Classifications of ABX- Agents that inhibit DNA processing by
Inhibition of DNA topoisonerases
Quinolones
Inhibition of DNA-dependent RNA polymerase (Directly-rifampin and indirectly- nitrofurantoin)
Classifications of ABX- The antimetabolites- blocking bacterial folic acid pathway
Trimethoprim
Sulfonamides
Methicillin-resistant Staphylococcus aureus (MRSA) and Mycobacteria tuberculosis
Multiple drug-resistance bacteria
Beta Lactam Compounds
Penicillins Cephalosporins Cabapenems Monobactams Beta lactamase inhibitors
Beta Lactam Compounds- Penicillins
Natural penicillin
Aminopenicillins
Penicillinase Resistanct Penicillins
Extended spectrum penicillins (Anti-psuedomonal)
Beta Lactam Compounds- Cephalosporin
First generation- fifth generation
Penicillins Mechanism of Action
Interfere with the last step in bacterial cell wall growth
Works best on rapidly proliferating organisms
No effect on organisms without a cell wall (protozoa, mycoplasma, mycobacteria, fungi, and viruses)
Penicillin resistance
Inactivated by beta-lactamase
Modification of PBP target (mechanisms of MRSA and penicillin resistant to pneumococci)
Impaired penetration of drug to target PBP
Penicillin classification- Natural Penicillins
Penicilling G or V
Narrow spectrum, PCN G acid labile, penicillinase sensitive.
Highly active against sensitive stains of gram positive cocci (Not staphylococcus)
Anaerobes
Some gram negative
Penicillin G or V
Tx infections of upper and lower respiratory tract, throat, skin, and GU tract.
Prophylaxis in rheumatic fever, dental procedure for those at risk of endocarditis, gonorrhea or syphilis expose.
Penicillin G or V- gram positive cocci
Streptococcus, enterococcus faecalis, listeria morlocytogenes
Penicillin G or V- Anaerobes
Bacteroides species and fusebacterium species
Penicillin G or V- gram negative
E. coli, H. influenzae, N. gonorrhoeae, Treponema be, and suspectible psuedomonas species.
Amniopenicillins
Ampicillin and amoxicillin
Ampicillin and Amoxicillin
Activity of PCN G plus improved coverage of gram negative cocci adn Enterobacteriaceae
Not active against treponema or actinomyces
Ampicillin and Amoxicillin- therapeutic uses
URI (Otitis, sinusitis), uncomplicated UTI, meningitis, salmonella infections
Ampicillin and amoxicillin- resistance leading to combinatins with beta-lactamase inhibitors
Augmentin = Amoxicillin + Clavulanic acid
Ampicillin + sulbactam (unasyn)
Better coverage against H. Influenzae and Klebsiella sp.
Penicillinase-Resistance Penicillins (antistaphylococcal penicillins)
Nafcillin, oxacillin, dicloxacillin
Methicillin and cloxacillin no longer available in US
Penicillinase resistance, narrow spectrum
Staph resistant to this class is called MRSA
Penicillinase-Resistance Penicillins (antistaphylococcal penicillins)- tx
Used in treatment of staphylococcal infection with high beta-lactamase production (cellulitis and endocarditis)
Not active against gram-negative or anaerobic organisms
Antipseudomonal penicillins
Piperacillin, ticarcillin, carbenicillin (PO)
Maintains activity of PCN G but gain great gram negative coverage including psuedomonas
Coverage against H. influenzae and kelbsiella sp
No coverage against treponema palladium or actinomyces
Gram negative infections in combo with aminoglycosides (bacteremias, pneumonias, resistant UTIs, infections in burn patients)
Antipseudomonal penicillins- resistance issues and are paired with beta-lactamase inhibitors
Piperacillin + tazobactam = zosyn
Ticarcillin + clavulanic acid= timentin
Beta-lactamase inhibitors
Clavulanic acid, sulbactam, tazobactam
Structurally similar but lack antibacterial activity
Act as suicide inhibitors -> potent, irreversible inhibitors of many lactamases.
Extends the spectrum of the ABX its paired with
Addition of Beta-lacamase inhibitors- Aminopenicillins
Amoxicillin + clavulanic acid (augementen)
Ampicillin + sulbactam (unasyn)
Addition of Beta-lacamase inhibitors- Antipseudomonal penicillins
Piperacillin + tazobactam (Zosyn)
Addition of Beta-lacamase inhibitors
Increased coverage against H. flu, staph, moraxella catarrhailis
Variable coverage against gram (-) bacteria- pseudomonas, enterobacter, E. coli, klebsiella, serratia due to resistance to these beta-lactamase inhibitors.
Penicillin pharmacokinetics-absorption
Many cannot be administered orally (due to destruction in acid)
Food may decrease the absorption of available oral penicillins
IV route bypasses absorption considerations and is preferred for serious infections.
Penicillin pharmacokinetics- Distribution
Widely distributed with tissue level=to serum
Poorly penetrate the eyes, CNS, and prostate
ONLY PENETRATE THE CNS WHEN MENINGES ARE INFLAMED.
Penicillin pharmacokinetics- metabolism
Most penicillins are not metabolized by dependent on the kidney for elimination
Penicillin pharmacokinetics- elimination
Kidney excretion is the main route of elimination (except antipseudomonal PCN and nafcillin via billiary excretion)
Penicillins are filtered (10%) and actively secreted (90%) into the urine
Active secretion can be blocked by probenecid
Doses need to be adjusted in renal insufficiency
Penicillins Adverse Effects
Hypersensitivity
Allergic responses develop in respinse to beta-lactam ring and derivatives (Cross rxn)
Anaphylactic shock is rare
Serum sickness- urticaria, rash, fever, angioedema
Interstitial nephritis and hemolytic anemia
Desensitization protocols are available.
Penicillins adverse effects
GI upset with oral agents
Diarrhea
Secondary infections- vaginal candidiasis
Hepatitis w/ oxacillin
Neutropenia w/ nafcillin
Abnormal platelet aggregation with ticarcillin and carbenicillin
Cephalosporins Intro
Discovered 1948 by Guisepee Brotzu
Similar to penicillins chemically, MOA, and toxicity
Bactericidal
Inhibit bacterial-cell wall synthesis similar to PCNS
Structurally contain a dihydrothiazine ring connected to the B-lactam ring making them more resistant to hydrolysis by B-lactamase (Broader spectrum of activity)
Classified by 5 generations
Category B in pregnancy
Cephalosporin Resistance
Mutations or carried on plasmids
Mutations in PBP
Production of Beta-lactamases
Alteration in cell-membrane porins in gram negative bacteria
1st Generation Cephalosporins Spectrum
Good aerobic gram-positive, above the diaphragm anaerobes and community acquired gram negative coverage.
Stable against staph produced penicillinase
IV= Cefazolin (Ancef)
PO= Cephalexin (keflex)
1st Generation Cephalosporins - Use
Used for septic arthritis in adults, skin infections, acute otitis media, prophylaxis for clean surgeries, and gram (+) infections in pts that cannot take penicillin
2nd Generation Cephalosporins- Spectrum
Two classes w/in second generation Added gram (-) coverage (ie moraxella, neisseria, salmonella, shigella, haemophilus influenzae) IV and PO= cefuroxime (zinacef, ceftin) Added anaerobic coverage (especially B. Fragilis) IV= cefotetan (cefotan)
2nd Generation Cephalosporins- Use
Added gram (-) IV and PO= cefuroxime (zinacef, ceftin) Useful for sinusitis, otitis, CAP Added anaerobic coverage IV- cefotetan (cefotan) Useful for tx of abd and gynecological infections
Summary of 2nd generation cephalosporins
Gram (+): 2nd generation < 1st generation (somewhat)
Gram (-): 2nd generation > 1st generation (Significantly)
3rd Generation Cephalosporins- Spectrum
Expanded gram-negative coverage and penetration of BBB
Cefpodoximine (Vantin), cefdinir (omnicef), cefixime (suprax)=oral
Cefotaxime (claforan)
Ceftriaxone (rocephin) = IV and IM
Ceftazidime (fortaz) distinguishes itself w/ increased anti-pseudomonal
3rd Generation Cephalosporins- clinical use
Used to tx a wide variety of serious infections caused by organism that may be resistant to other antimicrobial agents
Drugs of first choice in tx of meningitis, pneumonia in children and adults, sepsis, peritonitis
Tx of UTI, skin infections, and oesteomyelitis, Neisseria gonorrhea infections
Summary of 3rd generations cephalosporins
Gram (+): 1st generations > 2nd generation or 3rd generation
Gram (-): 3rd generation= 2nd generation > 1st generation
4th Generation Cephalosporins- Spectrum
Cefepime (maxipime) IM/IV
Good activity against both gram(+) and gram (-) bacteria; ALSO ANAEROBIC COVERAGE
4th Generation Cephalosporins- coverage
P. aeruginosa, H. influenzae, N. meningitidis, N. gonorrhoeae
Enterobacteriasceae that are resistant to other cephalosporins
4th Generation Cephalosporins- clinical use
Intra-abdominal infections, respiratory tract infections, skin infections
Summary of 4th generation cephalosporins
Improved gram (+) compared to 2nd and 3rd generations (Closer to 1st generation) Retain gram (-) = or > 2nd and 3rd generations
5th Generation Cephalosporin
Ceftobiprole medocaril
Approved March 2008
Tx of complicated skin and skin structure infections (MRSA)
Inhibits PBPs involved in cell wall synthesis
Well tolerated-nausea and taste disturbances
IV form only
Cephalosporins Pharmacokinetics
Orally administered absorbed rapidly
Presence of food may increase, decrease, or not affect absorption
Extensive distribution (most don’t cross CSF except cefuroxime, cefotaxime, ceftriaxone, cefepime)
Most eliminated via kidneys