Drug Flashcards

1
Drug Flashcards

• Respiratory system

2
H1 Receptors

• higher affinity for HIST than H2
• Mediates rapid onset but short-lived vasodilation
• Coupled to PLC, which hydrolyzes phospholipids to
  form IP3, DAG
• IP3 Ca activates MLCK and PLA2
• MLCK phosphorylates myosin causes
  bronchoconstriction, increased peristalasis
• PLA2 produces nitric oxide and PGI2
• DAG activates protein kinase C which facilitates
  Ca release from SR
• H1Antagonists 1st gen penetrate CNS hi SEDXN
• Considerable Anti-cholingergic effect
  anti-emetic
• Antihists cause CONVULSIONS in CHILDREN
• CNS stim restless, unable to sleep, halluc,
  ataxia

3
Antihistamines 1st gen

• Diphenhydramine
• Type I IgE mid hypersen rxn
• Motion sickness
• Nighttime sleep aid
• Antitussive
• Topical for itch
• CXN repeated topical use can cause allergic rxns

4
Antihistamines 1st gen

• Doxylamine (Unisom)
• Most sedating
• Dimenhydrinate OTC
• N, V, dizziness, vertigo
• Very sedating contains diphenhydramine

5
Antihistamines 1st gen

• Meclizine
• Motion sickness
• Long acting 12-24 hours
• Cyclizine
• Motion sickness
• Hydroxyzine
• Motion sickness
• Prurities
• Pre-op and post-op sedxn
• Anxiety

6
Antihistamines 1st gen

• Promethazine
• also blox alpha 1 Rs
• SEFX vasocon
• Type 1 hypersens allergic rhinitis
• Sedative pre/post-op obstetric sedation
• Anti-anxiety pre/post-op facilitate sleep
• Anti-emetic phenothiazine - blox D2 give
  pre-op, prevxn NV from gen anesthetics
• Motion sickness anti-hist, anti-cholinergic
• CXN lowers SZ threshold

7
Antihistamines 1st gen

• H1 Antagonists not much info
• Clemastine long acting, 12-24h
• Chlorpheniraine (Chlor-trimeton)
• Dexchlorpheniramine (Polaramine)
• Azelastine
• Phenindamine

8
Antihistamines 1st gen

• Cyproheptadine (Peractin)
• Shown to cause wt gain, block 5HT2 Rs.
• May be best to TX Itching
• Brompheniramine (Dimetapp)
• Available only with other ingredients
  pseudophedrine (Sudafed), APAP (Tylenol),
  dextromethorphan

9
Antihistamines 2nd Gen H1 Antas

• Poorly penetrate CNS, little or no SEDXN
• Fexofenadine ( allegra)
• Cetirizine (Zyrtec) metab of hydroxyzine,
  slightly sedating, long-acting 12-24hrs
• Loratadine (Claritin) stim appetite wt gain
• Desloratadine (Clarinex) isomer Loratadine
• Beta agonists with anti-HIST activity by blocking
  degranulation of mast cells
• Cromolyn
• Nedocromil
• Nothing to do with beta activity

10
Antihistamines H2 Antas

• Cemitidine (Tagament) Oral IV
• Tagament HB OTC
• Worst SEFX, but only in high doses binds to Cyt
  P450 significant inhibition Rx metab
• ? estradiol levels ? feminization
• Failure to hydroxylate to estriol (polar form)
• ? Prolactin gynecomastia
• Hi doses for Zollinger-Ellison Syndrom, tumor of
  pancreatic islets that cause secretion of
  sufficeint amt Gastrin to stimulate ACID
  secretion to life-threatening levels
• Inhibits conversion testosterone to
  dihydrotestosterone(DHT) in testes
• Inhibits binding of DHT to receptor impotence,
  less libido

11
Antihistamines H2 Antas

• H2 mediates slow onset but sustained
  vasodilation
• Does NOT mediate bronchoconstriction
• Stimulates adenylyl cyclase ? cAMP which
  activates PROTEIN KINASE that
• Phosphorylates and activates Ca pump that pumps
  Ca out of cell/into SR
• Phosphorylates and Inactivates MLCK prevents
  activation myosin
• Stimulating H2 Rs ? gastric acid secretion
• H2 Antas inhibit gastric acid secretion by
  parietal cells
• Change in acidity alters absorption
• Weak acid more ionized, less absorption
• Strong Base less ionized, MORE absorption

12
Antihistamines H2 Antas

• Nasal Decons alpha 1 constriction
• Phenylephrine(Neo-Synephrine)
• Shock, SVT vascon ??BP?BRR
• Ophthalmic mydriatic dilator muscle
• Added to local anesthetic keeps it local
• Ephedrine mixed alpha/beta agonist
• OCT nasal spray, jelly
• Alpha 1 nasal decongestant
• Beta 2 bronchodilator
• Pseudoephedrine (Sudafed) tablets, oral lq, ped
• Desoxyephedrine Vicks inhaler

13
Antihistamines H2 Antas

• Naphozoline (Privine) nasal drops and spray,
  ocular decon Naphcon
• Oxymetazoline (Afrin) drops and spray, ocular
  decon Ocuclear
• NOT alpha 1 agonist Alpha 2 diff R, same MOA
• SEFX hypoTN, pounding HR
• Remember CLONIDINE? Stim heart center in CNS,
  decreases SYM outflow, ?BRR
• Propylhexedrine (Benzedrex) Inhaler
• Subject to abuse amph-like efx
• Chronic abuse vent failure, pulm HTN, Sudden
  Death
• Tetrahydrozoline (Tyzine) drops and spray
• Xylometazoline (Otrivin) drops and spray

14
Expectorants

• MOA irritate lining stim secretions decrease
  viscosity
• Guaifenesin (Robitussin)
• Catogory I ingredients safe and effective for
  advertised use
• Only FDA approved for this
• Also claimed to decrease surface tension of
  mucous, decrease adhesiveness
• Robitussin DM dextromethorphan guaifenesin
  cough suppressant
• Best expectorant FLUIDS

15
General Anesthetics

• Nitrous Oxide
• good analgesic, weak anesthetic dorsal horn
• Analgesic effects in dorsal horn primary
  sensory nociceptive (pain) fibers synapse with
  projection fibers to brain
• cross-tolerance bt analgesic efx of NO and
  morphine analgesic eff NO can be blocked by
  NALOXONE
• NOT used alone bc even HIGH conc will NOT produce
  surgical anesthesia
• By using as adjuvant, can use less others,
• Decrease sefx both
• Low lambda low solub like Desflurane
• Rapid indxn, rapid recovery diffusional
  hypoxemia
• TOX neuropathies, anemias
• Interfere w/ folate, B12 metab, oxidizes cobalt,
  dec met syn
• Efx cummulative wait gt 3.4 days
• Abuse myeloneuropathic pernicious anemia

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• Halothane
• Hi lambda, slow indxn, slow recovery
• Non-irritating
• Mod skeletal mm relax
• No useful analgesia (use w Nitrous oxide)
• Low TI
• HypoTN vasodil, neg inotrop, neg chrono, dec BRR
  no reflex tachy, 20-50 dec CO, BP
• TachyARs Re-entry, inc automaticity
• Hep-TOX
• SL inc liver enzymes
• Hepititis w repeat admin
• Metab trifuoroethanol, BR- - tissue tox
• Induces change hep proteins, autoantibodies
• Malignant hyperthermia
• Ca activates myosin ATPase HEAT give
  DANTROLENE

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• Enflurane - most resp depress
• Mod analgesia
• Good mm relax
• Bronchodilator
• Metab ? fluoride nephrotoxic
• SZs on EEG
• Isoflurane most widely used
• Less resp depress
• Mod analgesia
• Good mm relax
• Bronchodilator
• ? flouroide
• No ICP neurosurgery
• Maintains CO, no ARs
• Pungent odor cough
• Coronary steal in IHD CONTRA malignant
  hyperthermia
• Methoxyflurane most potent
• Excellent analgesia
• Good mm relaxant

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• Desflurane LOWEST lambda
• Rapid indxn, recovery (like NO)
• Irritating hold breath, bronchospasms
• Mx out/in pt surgery, fast indxn desirable
• CONTRA malig hypertherm
• Sevoflurane very low lambda
• Rapid indxn, recovery (like NO)
• Pleasant odor good for kids
• Cxn reacts w soda lime prods nephroTOX
• In/out pt surgery

19

• IV anesth- ultra-short acting Barbs
• Thiopental unconcx 10-20 sec,
• Rapid indxn get past stage 2
• Inc GABA bind, gCl hyperpolarizes
• Resp depress, but venodilates - ? ICP
• Unique to thiopental ? BP, ? HR
• Hyperalgesic ? pain sens, sym response tachy,
  mydriasis, sweating, tachypnea, ?BP, mvt, vocaliz
• Release Hist apnea, coughing,
• CONTRAs porphyria periph, central neuropathies,
  abdom nerve damage, abdom pain, neuropsychiatric
• USE indxn, mx short procedures
• Methohexital ? risk cough, spont mvt gt thiopent
• BUT, no HIST release

20

• Benzodiazepenes
• ? safety margin, min CV, resp depress, excellent
  sed, amnestic,
• NO analgesic activity
• MOA ? gCl hyperpolariz - ? frequency
• Diazepam long-acting, active metabs
• Hi lipid solub, accum in adipose, Postanesth
  drowsiness,
• Problems propylene glycol
• CV collapse, irritates veins
• Midazolam non-irrate, better U/T after IM
• Short DOA no metabs
• Cimetidine, erythromycin inh metab oversedxn
• Lorazepam intmed-act, slow onset,
• Best for anxiety, sedation
• Triazolam anxiolytic, sed, amnesiac ORAL
• Prolonged sleep latency
• Flumazenil BZ ANTA rapidly reverse sed efx
  BZs
• Speed recovery of anesth

21

• Ketamine (misc)
• Deriv PCP (Angel dust)
• Dissociative Pt catatonic, analgesic, amnesic
• Eyes remain open
• MOA
• Blox NMDA Glut R
• Mu agonist activty analgesia
• Sigma/PCP Rs dysphoria
• Active metab unconcx after single bolus
• Analgesia 30-40 min
• Disadvantages
• Dilates cerebral vessels ??ICP
• Release catechol ??HR, CO, BP good for shock
• CONTRA CVA, hyper-T, IHD
• Emergence phenom coming out of anesth
• Disorientation, delirium, halluc control w IV
  diazepam b4 Ketamine
• Incidence less in KIDSlt15 yrs, elderlygt65 yrs

22

• Etomidate hypnotic indxn w rapid onset, short
  DOA,
• NO ANALGESIA
• Minimal CV, resp depress
• Disadvantages
• Hi NV, venous pain, thrombophlebitis, transiet
  myclonus, suppresses adrenocorticoid syn
• Propofol Sed-hyp indxn, mx
• Post-op nausea rare
• Sefx pain on injectin, use large vein
• 20-30 ?BP on indxn w/o reflex tachy
• From ? periph resist, strong (-) ino efx, inh BRR
• Apnea, SZs cxn epileptics
• CXN soybean vehicle excellent med bact growth!

23

• Opioid analgesics anal, sed, mood-alter, risk
  tolerance, depend, addict, ? MACs
• Morphine less soluble, 15-20 min 4 peak
• Pre-op sed, anal, allay anxiety, post-op anal
• Resp depress, hist release, supresses cough
  reflex cxn asthma, resp dx
• HIST vasodil, hypoTN w reflex tachy
• Meperidine 1/10 as potent morphine
• Shorter acting,
• vagolytic properties dry scrxn, tachycard
• hypoTN (-) ino, ? vasc resist, inh BRR tachy
• Resp depress??ICP
• Metab to NORMEPERIDINE CNS stimulant, convul
• Accumulates prolonged admin, ? hep/renal fxn
• Severe resp depress, halluc, SZs
• Do not give with MAOI 5HT SX

24

• More opioids
• Fentanyl quick, more potent MORPH
• Pre-op/Post-op anal, sole anesth sometimes
• No HIST release
• Fentanyl transderm patch chronic pain malig
  variable absorp TOX
• Fentanyl transmucosal
• Lozenge absorbed thru oral mucosa
• Pre-op, conscious sedxn HOSP use monitor
  breath
• Lozenge on a stick
• Break-thru CA pain pts tolerant other opiods
• Sufentanil mu R, 5x gt fen, anal, sole
• Alfentanil less potent, shorter DOA
• Endotracheal 1ary
• Remifentanil Fen ester, t ½ 10-15 min, adjunct