Pharmacology of Smoking Cessation & Antimicrobials Flashcards
smoking cessation - general principles
*need drugs + behavioral counseling
*drugs available include:
-nicotine replacement therapy (NRT) [usually long-acting (patch) + short-acting agent]
-varenicline
-bupropion
nicotine transdermal patch (long-acting)
*provides constant level of nicotine (highest strength provides nicotine plasma level ~50% of smoking 20 cigarettes per day)
*easy to use, high compliance rate
*best success if combined with short-acting product
*slow onset (about 3 hours)
*can’t adjust dose throughout day based on craving
*main ADE is local skin irritation
*sometimes used for nicotine-addicted hospitalized patients who are admitted for other reasons
short-acting nicotine replacement therapy (NRT) - general principles
*should be used in combination with a patch
*dosed multiple times during day (can adjust based on cravings & withdrawal symptoms)
*absorption needs to occur prior to nicotine getting into esophagus (nicotine is metabolized by liver and little is absorbed)
*4 options: gum, lozenge, inhalers, nasal spray
nicotine gum
*a short-acting nicotine replacement therapy (NRT) agent
*nicotine blood levels within 20 minutes
*absorption from buccal mucosa
*most ADEs are from chewing too vigorously and getting bolus release of nicotine (nausea, vomiting, abdominal pain; esophageal, oral, & gastric irritation)
*avoid acidic beverages (lowers pH, ionizes nicotine, prevents absorption)
nicotine lozenge
*a short-acting nicotine replacement therapy (NRT) agent
*similar pharmacokinetics and uses as gum
*better if dental or TMJ problems
*ADEs:
-local = mouth irritation & ulcers
-nicotine-related = nausea, vomiting, abdominal pain, headache
nicotine inhalers
*a short-acting nicotine replacement therapy (NRT) agent
*plastic that contains nicotine cartridge
*better mimics sensory aspects of smoking
*inhale nicotine vapor (not smoke)
*absorbed through oral mucosa (not lungs)
*ADEs: throat & mouth irritation, bronchospasm
*not a great choice if you have asthma
nicotine nasal spray
*a short-acting nicotine replacement therapy (NRT) agent
*absorption via nasal mucosa:
-more rapid than other products
-peak blood levels in 10 minutes
-closer to the “hit” you get from smoking
*ADEs: nasal & throat irritation, rhinitis, sneezing
varenicline
*used for smoking cessation
*partial agonist for alpha-4-beta-2 nicotinic ACh receptor
*a slight agonist effect, but mostly blocks binding of nicotine to receptor (prevents stimulation of mesolimbic dopamine system that reinforces smoking)
*start taking 1 week prior to quitting smoking
*ADEs:
-GI: nausea, vomiting
-neuro: abnormal dreams, HA, insomnia
-severe neuropsychiatric and cardiovascular concerns not born out
bupropion for smoking cessation
*MOA: weak inhibitor of DA and NE uptake
*MOA in smoking cessation not entirely understood
*start taking 1-2 weeks prior to quitting smoking
*CONTRAINDICATED IN SEIZURE DISORDERS
*blunts post-cessation weight gain
*ADEs: insomnia, agitation, dry mouth, headache, lowers seizure threshold
predominant treatment of viral respiratory infections
*mostly supportive care (treat pain, congestion, cough, etc)
*2 viruses we have antivirals for: influenza & SARS-CoV-2
neuraminidase inhibitors for influenza
*MOA: inhibit influenza virus neuraminidase; this DECREASES NEW VIRUS PARTICLE RELEASE
*3 main products:
1. oseltamivir
2. zanamivir
3. peramivir
oseltamivir
*neuraminidase inhibitor used for influenza
*ADEs: nausea, vomiting, headache
uses of neuraminidase inhibitors for influenza
*shortens duration of flu symptoms (0.5-3 days) and reduces complications in high-risk patients
*give as early as possible (hopefully within 48 hours) to at risk patients
*can consider for healthy patients if within 48 hours of symptoms
*can sometimes use oseltamivir & zanamivir for prophylaxis
zanamivir
*inhaled neuraminidase inhibitor used for influenza
*ADEs: bronchospasm, sinusitis, dizziness, ENT infections
peramivir
*IV neuraminidase inhibitor used for influenza
*ADE: diarrhea
remdesivir
*an antiviral used for COVID (infection caused by SARS-CoV-2)
*MOA: nucleotide analogue (of ATP) which inhibits RNA-dependent RNA polymerase
-competes with natural ATP for incorporation into RNA, leading to delayed chain termination during replication of viral RNA
-prodrug; needs to be activated to triphosphate
*ADEs: nausea, elevated transaminases
*best if used early in the disease
nirmatrelvir/ritonavir (Paxlovid)
*an antiviral used for COVID (infection caused by SARS-CoV-2)
*MOA: both are protease inhibitors:
-nirmatrelvir: inhibits SARS-CoV-2’s main protease (Mpro)
-ritonavir: inhibits metabolism of nirmatrelvir (acts as a booster; watch for drug interactions)
*used for symptomatic patients at risk of progressing to severe disease
drugs that treat/prevent inflammation associated with COVID (not the virus itself)
*Baricitnib (JAK inhibitor)
*Tocilizumab (IL-6 receptor antagonist)
*Dexamethasone (& other steroids)
*these treat/prevent the inflammation and tissue destruction caused by the virus, NOT the virus itself
beta lactam antibiotics
*penicillins, cephalosporins, monobactams, carbapenems
*MOA: bind to penicillin-binding proteins (PBPs), which are enzymes involved in peptidoglycan biosynthesis, which provides the cross-linking structure essential for cell wall rigidity and stability
*inhibit cell wall synthesis (inhibit transpeptidation of peptidoglycans)
activity of beta lactams
*NO beta lactams are effective against:
-MRSA
-atypical organisms (mycoplasma, legionella, chlamydia)
natural penicillins (Pen G & Pen V) - spectrum
*strep pneumo
-good; a little resistance
*strep pyogenes (group A strep)
-NO resistance
aminopenicillins - spectrum
*ampicillin (IV) & amoxicillin (PO)
*coverage: like natural penicillin (strep pneumo, strep pyogenes) PLUS:
-E. coli (60%)
-Proteus mirabilis
-H. influenzae (70%)
clinical uses of amoxicillin
*target S. pneumonia & H. flu:
-otitis media
-other community-acquired respiratory infections
*alternative for strep throat