DRUGS

Drugs with a narrow TI

Digoxin (Lanoxin) - MI in overdose
Warfarin (Coumadin) - anticoagulant, bleeding in OD
Phenytoin (Dilantin)
Tacrolimus (Prograf, Astagraf) - immune suppressant
Toxicity is easier to reach when administering these drugs!

Drugs that are extensively PPB (>90%)

Warfarin (Coumadin)
Ibuprofen & naproxen (NSAIDs)
Furosemide - loop diuretic
Digitoxin (CV drug)

1st gen antihistamines

Diphenhydramine (Benadryl, Allerdryl)
Chlorpheniramine (Ingredient)
Known to have CNS effects (crosses BBB) so side effects include drowsiness

2nd gen antihistamines

Fexofenadine (Allegra)
Loratadine (Claritin)
Cetirizine (Reactin - onset 10-20 min, duration 24hrs)
Desloratadine (Aerius)
No CNS effects

Antitussives

Relieve or suppress coughing by depressing the cough reflex in the medulla of the brain
Codeine
Dextromethorphan (direct CNS acting)

Anti inflammatory asthma drugs

Glucocorticoids
Leukotriene modifiers
Mast cell stabilizers

Glucocorticoids

**suffix -one**
Liphophilic, high PPB, long DoA. Given once/twice a day, many side fx due to their MoA.
Hydrocortisone, cortisone
Prednisolone (prodrug!)
Methylprednisolone
Dexamethasone (systemic)

Glucocorticoids for allergic rhinitis

Budenoside (Rhinocort, Pulmicort {inhaled})
Fluticasone (Flonase, Flovent {inhaled})
Mometasone (Nasonex)

Tacrolimus

Prograf, immune suppressant

Cell wall synthesis inhibitors

Bactericidal;
Carbapenems
Penicillins
Cephalosporins
Bacitracin
Vancomycin

Beta lactam antibiotics

Bactericidal;
Penicillins
Cephalosporins
Carbapenems
- Prone to resistance developing

Penicillins

**-illin suffix** (generic names)
Cell wall inhibitor
Broad spectrum, effective on both G+ & G- but depends on which penicillin is used
10% of ppl have a cross allergy to penicillins and cephalosporins

Penicillin family tree

Goes from narrow to broad spectrum
Penicillin G & V > Methicillin & Ampicillin > Amoxicillin > Piperacillin

What can penicillin be used to treat

Pharyngitis caused by S. pyogenes - give Penicillin V PO
Otitis media caused by S. pneumoniae, Hib, Moraxella - give Amoxicillin PO

Clavulanic acid and Tazobactam

Beta-lactamase inhibitors
Can be combined into Amoxicillin, Ticarcillin and Pip taz

Co-amoxiclav

Amoxicillin + clavulanic acid
Brand name Augmentin

Co-ticarclav

Ticarcillin + clavulanic acid
Brand name Timentin

Pip-taz

Piperacillin + tazobactam
Brand names: Tazosin, Tozyn
Broad spectrum penicillin

Cephalosporins

**cef- prefix**
Cell wall inhibitor
biggest antibiotic class w/ 5 gens. Lower the gen, lower Vd
Might work on MRSA/resistant bacterial infx.

Examples of cephalosporins

1st choice for skin infections
Cefazolin (Ancef, IV)
Cephalexin (Keflex, PO)
Cefuroxime

Gen 3-5 cephalosporins

Can cross the BBB
**prefix ceft-**
Ceftriaxone, Ceftazidime, Ceftaroline
Effective against bacterial meningitis

Carbapenems

**-penem suffix**
Cell wall inhibitor
Potent, NOT 1st line therapy - given IV to super sick ppl/more than 1 pathogen
eg Imipenem, Meropenem

Bacitracin

Cell wall inhibitor, super common
Broad spectrum but used for G+. Prophylactic, used to treat conjunctivitis and skin/soft tissue topical infx.
Eg polysporin

Vancomycin

Cell wall inhibitor. Reserved for IV + superinfections. 1st choice for MRSA/staph aureus infx, 2nd choice for C.diff

Protein synthesis inhibitors

Chloramphenicol
Aminoglycosides (Erythromycin, Streptomycin)
Tetracyclines
Macrolides

Macrolides

**-romycin suffix**
Protein synthesis inhibitors
good for specific treatment, 1st choice for community acquired adult pneumonia
Can treat gonorrhea if combined with a cephalosporin but resistance is increasing)

Examples of macrolides

Erythromycin (PO, combined w/ ceftriaxone IM)
Azithromycin (Zithromax for pneumonia)
Clarithromycin (Biaxin)

Tetracyclines

**-ycline suffix**
Protein synthesis inhibitors
Broad spectrum, these mfs existed for a long time
side fx: bone deformations & tooth discoloration b/c they bind to calcium in fast replicating cells, like in kids/teens

Examples of tetracyclines

Tetracycline, Doxycycline, Monocycline

Aminoglycosides

**mycin suffix**
Protein synthesis inhibitors
Highly potent, IV only - give during severe infx. only
Tobramycin eye drops can be used for conjunctivitis
Side fx are cytotoxicity and risk for hepato/neurotoxicity

Lincosamides

Often used as alternatives for ppl who are allergic to penicillin
eg Clindamycin

Clindamycin

a LINCOSAMIDE!!! not an aminoglycoside!!!!
Used for surgical prophylaxis, 1 day before and 2-3 days after surgery

Nucleic acid replication/transcription inhibitors

Quinolones, Rifampin

Fluoroquinolones

**-xacin suffix*
High efficacy for G-'s (GI, UTI infx.) can become a systemic prodrome of symptoms

Examples of fluoroquinolones

Ciprofloxacin
Levofloxacin
Norfloxacin

Ciprofloxacin

Good PO (little 1st pass metabolism losses) and IV. Good bioavailability (70%), and good metabolite after phase 1 metabolism b/c it continues to produce effects (but less potent)
Directly binds to bacteria in GI
CYP inhibitor
Renally excreted and some thru bile
Half life 4hrs

Nitroimidazoles

DNA synthesis inhibitors
Not sure about suffix..
Eg Metronidazole (Flagyl)

Metronidazole

Flagyl, effective against C. diff (1st choice), H. pylori, and prophylaxis for dental

Antimetabolites

Inhibit synthesis of essential metabolites = kill bacteria from inside
Sulfonamides, Trimethoprim

Sulfonamides

**sulfa- prefix**
1st effective antibiotics made but used for UTIs now
Cause precipitation in urine = kidney stones = need to encourage high intake of water
Be careful when giving to people w/ hypertension, can lead to congestive heart failure

Examples of sulfonamides

Sulfamethoxazole, t-sulfamethoxazole (TMP/SMX, Bactrim, Septra)
Nitrofurantoin -- activated by bacteria, combine meds w/ this for synergy

General side effects for drugs

GI disruption -- diarrhea, abdominal pain, nausea
Superinfections -- w/ broad spectrum antibiotics, like c diff
Drug-drug interactions -- take precautions esp. in contraindications

Common drug allergies

Penicillins, cephalosporins and sulfa drugs

Polyene fungal antibiotics

Target fungal infx like Cryptococcus, Candida, and Aspergillus. Increase cell membrane permeability to make it more porous

Examples of polyene fungal antibiotics

Azoles:
-Amphotericin, 1st choice thru IV but can also be used as mouthwash
Polyins: used for Candida skin/GI infx, given PO

Tuberculosis meds

Rifampin - DNA inhibitor
Isoniazid - cell wall synthesis inhibitor
^ are combined and other meds can be added in too

Antivirals

**-vir suffix, but not all**
Attack virus before it gets to host cell; use a series of antivirals to attack at different stages
HIV, herpes and flu antivirals are available

HIV antivirals

Cocktail of 4-5 drugs PEP (post exposure prophylaxis) - triple therapy x28 days, max 72hrs to initiate.
HIV harbors in lymph tissue and any IV won't get to it quick enough therefore it can be fatal or result in nosocomial infx.

Herpes virus antivirals

HSV-2 can be treated with acyclovir - PO, IV, cream
Herpesvirus 5/CMV can be treated using Ganciclovir

Influenza antivirals

Tamiflu and Amantadine - decrease severity of disease and lower virulence, doesn't treat the actual flu though

Treatments for H pylori

Omeprazole
Clarithromycin
Amoxicillin

H2 receptor antagonists/blockers

H2 specific. Results in decreased HCl production. Quick relief & used for acute treatment - IV
Eliminates histamine triggers but NOT gastrin therefore we still produce HCl, just not as much

Examples of H2 receptor blockers

Ranitidine (Zantac) - doesn't cross BBB , no side fx like headaches
Cimetidine (Tegamet) - crosses BBB. Used for quick relief, unscheduled
Famotidine (Pepcid)

Proton pump inhibitors

Bind to HKATPase enzymes to inhibit HCl acid secretion. More effective than H2 receptor blockers, half life/onset is longer too (3 days onset) - used for chronic relief
Lower dose is better so we still have HCl present.
If situation is acute we can start with H2 blockers then transition into PPIs
But we see malabsorption - no chemical digestion & no conversion of elements into active metabolites

Antacids

Short term relief, alkaline agents increase stomach pH but don't decrease HCl secretion. All based on mineral elements

Antacid meds

Aluminium hydroxide (Amphojel, can cause constipation)
Magnesium hydroxide (milk of magnesia, can cause diarrhea)
Calcium carbonate (Tums, Caltrate, can cause high calc. in blood)
Pepto-bismol (Bismuth Subsalicylate, causes platelet inhibiton + anti diarrheal b/c stimulates fluid absorption thru intestinal wall, inhibitory to H pylori growth too)
Rolaids, Maalox, Sodium bicarbonate (Alka seltzer), Eno, Diovol

1st line therapy for PUD

3 antibiotics x 2 weeks
Amoxicillin + Clarithromycin (can substitute either with Tetracycline if allergic) + Metronidazole (flagyl)
+
PPI to decrease acidity to protect the ulcer from degrading further, eg Losec (Omeprazole)

Bismuth therapy for PUD

Antibiotics + bismuth subsalicylate (peptobismol) - peptobismol is used instead of PPIs and inhibits bacteria growth + mucosal adhesion

Lactobacillus acidophilus

BioK+ - probiotic. Start after antibiotic treatment is finished
Destroys other bacteria like E coli by secreting hydrogen peroxide, restores + protects normal flora

Antidiarrheals

Trigger Mu2 receptor which triggers decreased peristalsis. CNS side fx - depression in high doses b/c it binds to similar receptors as opioids; careful when giving in pregnancy and drug abuse!

Examples of antidiarrheals

Opioid + atropine
Dyphenoxylate (Lomotil)
Loperamide HCl (Imodium)
Meperidine (Demerol, active ingredient) + Atropine
Low doses OTC, can be higher doses Rx

Atropine

Antimuscarinic, blocks parasympathetic system + stimulates sympathetic drive. Antagonizes muscarinic receptors = less activity + peristalsis

Bulk forming laxatives

Metamucil (Psyllium) - fiber that increases bulk + pulls in water, used best prophylactically. Onset is 1-2 days. Water intake is a must. Mostly PO and some PR, available unscheduled, and used long term in nursing homes

Softener laxatives

Docusate sodium (Colace) - electrolyte based, pull water and fat into stool. Used prophylactically. Need good renal fx for excretion; mainly used post M.I. and post surgery

Docusate calcium & sodium

Calcium PO + sodium PO and PR. Minimally absorbed + exert effects locally; some systemic absorption happens in jejunum and duodenum but extent is unknown and probably insignificant and is then excreted in bile
Softening begins 1-3 days following initiation of administration PO

Saline & osmotic laxatives

Milk of magnesia, Lactulose, GoLytely. Pull water into stool, pre procedure is best. POTENT ACT FACT!!

Milk of magnesia

Preferred; very productive, acute, need to assess for good renal function b/c it's renally excreted

Lactulose

Not absorbed, contraindicated in lactose intolerance since some lactaid is present & pt's can bloat. Slow onset. PO or PR to prevent complications of liver disease, doesn't cure the problem but can improve mental status
A colonic acidifier that works by decreasing the amnt of ammonia in the blood

Stimulant laxatives

Increase peristalsis by irritating GI.
Dulcolax, Senna (herbal. Exlax, Senokot), castor oil
Side fx include N&V, cramping. Don't use if obstruction is possible b/c perforation can happen! Not first choice prophylactically or for constipation b/c of its side fx. Good for occasional bouts of constipation. Used when pt. is on fluid restriction + can combine w stimulant

Misc/lubricants

Given rectally to lubricate stool
Mineral oil, Glycerine
Adjunct treatment w/ constipation

Gasex

Can be given when a pt. is bloating. Bloating happens d/t a lack of enzymes/digestion so gasex supplements what's missing

Treating motion induced, morning sickness and anticipatory nausea

Antagonize H1 - antihistamines. Antagonize within cerebral cortex (vestibular) so it needs to be big in presence and distribution. Reduce vestibular excitation!!

Meds to antagonize H1

Dimenhydrinate (Gravol = diphenhydramine + chlorotheophyline)
Meclizine (Dramamine) - watch distribution in CNS
Diclectin = doxylamine + pyridoxine
Hydrochloride (vit. B6)

Ginger

High efficacy for motion sickness! Ginger gravol given as NHP, increases intestinal peristalsis -- empties the stomach so there's nothing to vomit. Safe in moderate doses but in OD we see bleeding d/t it being an anticoagulant, as well as CNS depression

Treating motion sickness

Antimuscarinics and anticholinergics. We need to reduce vestibular excitation
These meds have some cross affinity to H1 receptors -- secondary binding b/c they're similar receptors

Motion sickness med example

Scopolamine (Hyoscine) - antimuscarinic
Transdermal patch
IV, PO can be good for prophylaxis; reduces trigger mechanism and the vomiting later on

Treating drug induced/chemotherapy vomiting

Drugs/chemotherapy strip mucosa in the GI tract which triggers the vomiting mechanism, and we can antagonize it:
5HT3 (serotonin) antagonists
Ondansetron (Zofran) -- Rx only, PO/IV. Potent but works well!

Treating GI pain induced vomiting

D2 receptor antagonism: stimulates GI motility
NJ tube: we need good motility and sphincter relaxation to do this
Med class: Phenothiazines

Phenothiazines

Stimulate GI motility
Metoclopramide (Maxeran, Reglan)
Prochlorperazine (Stemetil) - lowers dopamine
Rx only: PO/IV
Side effects are sedation b/c we're antagonizing D2 in the CNS

Treating chemo, chronic disease and other challenging cases induced vomiting

CB 1 & 2 antagonism
Cannabinoids bind to CB1&2 receptors. Agonizing them inhibits serotonin which therefore calms the GI
CBD doesn't have as high efficacy as THC
Receptor binding stimulates GABA as a secondary effect -- inhibitory effects in CNS + sympathetic activity
Not 1st choice b/c long term we see decreases in productivity, short term memory deficits, depression, insomnia, headaches, etc.

Cannabis meds

Dronabinol (Marinol), Cesamet (Nabilone), Cannabis

Plasma expanders

Colloids; supply proteins into ECF and stay in circ.
Used when treating hypovolemic shock, but is contraindicated in most other cases d/t no pass via capillaries and the renal workload; good renal fx only tolerates it for so long
Plasbumin, Alburex

Crystalloids

Supply H2O, electrolytes and other solutes. Can move btwn ECF & ICF; tonicity directs fluid movement, especially the Na amount & glucose

NS 0.9%

Isotonic - #1 choice for resuscitation fluid
154 mEq Na, 154 mEq Cl
Has no nutrients so the patient can become deprived over a long time - side effects such as hypokalemia

Lactated Ringers (LR)

More electrolytes than NS!
Isotonic -- crystalloid, good for maintenance
Calcium 2.7mEq, Potassium 4mEq, Lactate 28mEq (alkaline in blood and can cause metabolic changes), Chloride 109mEq, Na 130mEq
S/e: hyperkalemia, high lactate
Contraindicated for peds d/t the high lactate and high electrolyte content

Other isotonic fluids

5% albumin - colloid
Dextran 40 - colloid
Both are isotonic but are hypertonic when in the body

D5 .45NS

Basically half of normal saline: 77mEq Na, 77mEq Cl, 50mEq dextrose
Hypertonic in the bag (405mOsm/L)
S/e: cellular dehydration, hyponatremia
1st choice maintenance fluid in peds but check K+ levels!

25% albumin

Colloid, hypertonic
25% albumin, up to 160mEq Na
IV volume expander; 3.5x its volume of additional fluid into circulation within 15 mins. Steals a lot of fluid at a high rate!
Can mix and match albumin & NS to avoid cell shrinkage and resulting organ damage

Other hypertonic fluids

D5NS
D5LR
D10W
3% NaCl - used in head injuries to lower ICP/cerebral edema

Hypotonic fluids

0.45NaCl
D5W
3.3% dextrose, 0.3% sodium
D5 0.2% NaCl
Can give to someone with hypernatremic dehydration (give D5W b/c of the high sodium)

What to give during blood loss

Packed RBCs -- contain formed elements to maintain osmolality
Whole blood -- not 1st choice b/c it has antigens, which can result in allergies
FFP -- fresh frozen plasma, contains coagulation factors

Direct acting vasodilators

ER use mainly
Stimulate endothelial cells to produce nitric oxide
Nipride (Nitroprusside) IV/ET
Hydralazine PO/IV -- not main stay treatment but can use it for a little longer
IV t1/2 is 2 mins

Diuretics

Decreases circulating blood volume = lowers BP = decreases H2O and electrolytes
1st line in HTN treatment!
4 types: loop, thiazides, potassium sparing, and osmotic

Loop diuretics

Work in the loop of henle; block Na, Cl, K reabsorption = more out with water
Furosemide (Lasix) -- 1st line therapy for HTN
Potent, IV/PO. Can be given PO for sudden onset, surgery, or past trauma
S/e: hypokalemia, ototoxicity, drug ints d/t high PPB.

Thiazides

Work in the distal convoluted tubule; decrease in reabsorption of Na, Cl, K = more out with water
Hydrochlorothiazide (HZTZ)
Chlorothiazide (Diuril)
Metolazone (Zaroxolyn)
S/e: hypokalemia

Potassium sparing diuretics

Aldosterone antagonists
Work in the collecting distal tubule; antagonizes renal aldosterone = increased Na out & keeps K+ in
Spironolactone (Aldactone)
t1/2 1-2 days; we see diuresis for longer than loop diuretics (Lasix)
S/e: hyperkalemia

Diuretic combo

Aldactazide: thiazie + potassium sparing
Used very frequently, balances out K, PO, excellent maintenance therapy for HTN

Osmotic diuretics

Mannitol (Osmitrol), Isosorbide
High solute, travel unchanged - continuously pull water w/ it = diuresis. Also increases BP
Pulls water into circulation and renal tubules (proximal tubule and loop of Henle)
Inhibit renin release
Used to treat cerebral edema and intraocular hypertension. Low CV use

Angiotensin converting enzyme (ACE) inhibitors

Inhibit ACE = vasodilation
1st line in heart failure = high efficacy and potency
**Suffix -pril**
Enalapril (Vasotec)
Captopril
Monopril
Ramipril (Altace)
s/e: severe hypotension

Angiotensin II receptor blockers (ARBs)

Lower blood pressure by blocking the angiotensin II enzyme from causing vasoconstriction = vasodilation!
decreased afterload = decreased preload
Takes a few weeks to take full effect
-sartan suffix
Losartan (Cozaar), Ibesartan (Avapro)
s/e: hypotension