OTC Agents Flashcards
Antacid Medications
- three common ingredients
- when/how they should be used
- how they work
- specifics of magnesium and aluminum preparations
Antacid Medications
how they work = they are buffering agents; which change the pH in the lower esophagus, stomach and duodenal bulb to decrease aciditiy
Relief = within 5 minutes, last for 20/30 quick onset
Indications = for mild, infrequent heartburn pt. using these more than 2x a week or regularly for more thant 2 weeks should see a provider for workup
Agents: Ingredents
Calcium Carbonate
Magnesium
Aluminum
Sodium bicarbonate
magnesium and aluminum = liquid preparations which covera greater surface area
chloride will react with cations, hydrogen will react with anions
Side Effects of the following Antacid Medications
- calcium carbonate
- magnesium
- aluminum
- sodium bicarbonate
renal dosing consideration
adsorbition/chelation consideration
Calcium Carbonate
- Beltching and flatulence
Magnesium
- Diarrhea
Aluminum
- Constipation
Sodium Bicarbonate
- Fluid Retention (watch in fluid overload/edematous; CHF,tc.)
- flatuence and beltching
Renal Impairment
- watch all these in those with CrCL < 30 ml/min
Chelation Consideration
- can adsorb to other medications
- separate from ABX (tetracycline, azithro & florquinolones) by 2 hours
- separate from levothyroxine by 4 hours
- separate from fungal oral agents by 2 hours
Histamine Type 2 Receptor Antagonists Medications
- names (which to use over others)
- how do they work
- when are they used/onset
Histamine Type 2 Receptors Antagonists
- famotadine : preferred agent
- cimetidine (not used)
- rantidine (off market)
How they work
- they bind to H2 receptors on parietal cells within the stomach to decrease the activation (not entirely eliminate) of parietal cells in producing HCL
When they are used
- they are good for mild-moderate heartburn prophylatically before the heartburn occurs
- take 30-45 mins to work; last 8-10 hours
- good for nighttime symptoms
Histamine 2 Receptor Antagonists
Pearls (when to refer)
renal considerations
D-D interations
Pearls
- should not use more thant 2x daily
- if using them PRN; they will work less
- if they need this more than 2 weeks of use = refer to be worked up
Renal Considerations
- adjust dose in those with CrCL < 50
- adjust in older pt.
D-D interactions
- most with cimitidine : so just avoid the med all together
Proton Pump Inhibitors
- how long can they be taken before needing eval.
- how long to wait betweedn a d/c PPI and started OTC antacids
- which PPI’s are offered OTC
PPIs
- can be used for 14 days without a rx. before they need to be evaluated for underlying disease (can use like a trial of PPI to dx. ulcer or self treatement of acid reflux)
- must wait 4 months between the d/c of a PPI and using antacids
if pt. needs relief sooner than 4 months, theres something going on and they need to see a provider
PPIs offered OTC
- omeprazole
- esomeprazole
- lansoprozaole
PPIs (OTC)
- how do they work & when used
- onset and duration
OTC PPI
- omeprazole
- esomeprazole
- lansoprozole
How they Work
- they irreversibly bind to the proton pump within the stomach: thus completely supressing the gastric acid secretion
- they will only bind to actively secreting proton pumps, so need to take them 30-60 mins before a meal
Onset & Duration
- slow onset 2-3 hours
- peak effect 3-4 days of thearpy
cannt be crushed, they wont work
PPI ADRs
- short term side effects
- longer term side effects
- chronic use side effects
Drug interactions via CYP 2C19
Short Term
- diarrhea, constipation
- headaches
Long term
- osteoporosis & fracture risk increases
Chronic use
- increased infection risk CAP and C. diff
- malabsorbition!!! : VitB12, iron, calcium & Mg (because working in stomach)
acid rebound can occur if continued use for > 8 weeks
Drug Interactions
- watch with clopidogrel: its a prodrug, so these meds will prevent conversion of clopidogrel to its active form: especially omeprazole and esomeprazole
Alpha-galactosidase (Beano)
- when is it used
- how does it work
- what is the gold standard in this class of meds
- caution in…
Alpha-glactosidase
when is it used
- to reduce gas: prophylatic for foods which contain oligosaccharides (complex carbs)
How it works
- galactosidase is the enzyme needed to breakdown complex carbs
Gold Standard: is simethicone (a surfactant med which probably is gold standard)
lactose intolerace? give them lactase enzymes (lactaid)
do not use in….
- glactosemia pt.
- those with DM
Laxitives
MOA accoding to each medication
Psyllium
Docusate sodium
mineral oil
polyethylene glycol
senna
Milk of Mag.
Psyllum
- a bulk forming laxative: increaes the stool’s retention of water, thus increasing rate of transit
Docusate Sodium
- stool softener: mixes aqueous and fatty substances together in the intestinal tract
Mineral Oil
- coats/lubercates stool to prevent colonic absorbtion & slide through GI tract
PEG
- osmotic laxitivate : pulls water into the RECTUM, thus facilating the passing of stool
Senna & Biascodyl
- stimulant laxitive: increases peristalsis by local irritation of nerves to increase movement in the GI
Milk of Magnesia
- fastest clearance: saline: most potent lax
- like a bowel prep for colonoscopy
- not for chronic manamagement
Laxitives
onset of action
psyllium
docusate sodium
mineral oil
polyethylene glycol
senna
Psyllium
- 12-72 hours
- bulk forming
Docusate sodium
- 12-72 hours
- softener
Mineral Oil
- 6-8 hours
- lubricant
PEG
- 12-72 hours
- osmostic agent
Senna
- 6-10 hours
- stimulant
Loperamide: Treatment of Diarrhea
MOA
dosing considerations (max)
role in therapy/when is it used
Loperamide (Imodium A-D)
- anti-diarrhea agent
- MOA: works as a synthetic mu opioid agonist: which opiods decrease the intestinal motility & thus decrease the diarrheal symptoms –: allowing more absoroption of electrolytes and water
Dosing Considerations
-NO more than 8 mg/day
shouldnt use for more thatn 48hours
Role in Thearpy
- should be used first-line gold standard for acute diarrhea (think IBS-D or traveler’s diarreha with abx.)
- not for kids < 6
NEVER USED IN C. DIFF PTS!!!! :toxic megacolon risk
ADR
- constipation
Prevention of Traveler’s Diarrhea
- medication to use
- how it works
- other indiciations for this medication
- adverse reactions
Medication for prophylatic traveler’s diarrhea : Bismuth Subsalicylate (pepto-bismol)
MOA: reacts with HCL to form bismuth oxycholride and salyclyic acid
- the bismuth has antimicrobial effects (locally in GI)
- the salicylic acid has antisecretory (antinflammatory- systemic) effects
- in traveler’s diarrhea, the salcyliate activity here seems to prevent the effect from occuring if contaminated
Role in Therapy
- for prophlyatic traveler’s diarrhea
- heartburn
- upset stomach
- indigestion
- nausea
Guidelines
- NEVER FOR KIDS: salycliate!!! reye’s syndrome
- not for this with asprin allergy: salycilayte
- not for pregnant: salycilate
ADR
- black stool or darkening of the tongue : will resolve
Lactaid
used for those with lactose intolerant
helpful to take with dairy products: help decrase the osmotic diarrheal effect
Antihistamines: H1 antagonists
First generations
second generations
how they work & their differences
First Generations Oral Antihistamines
- more drowsy, cross BBB
- Diphenhydramine
- chlorpheniramine
- celmastine
Second Generations Oral Antihistamins
less drowsy, peripherally selective
- loradidine (claratin)
- desloradidine (clarinex)
- cetirizine (zyrtec)
- levocitirizine (xyzal)
- fexofenadine (allegra)
MOA
- H1 histamine antagonists: to help decrease histamine response of sneezing, rhinorrhea, itchy & eye symmptoms
- better for prevention that relief: aim to take before exposure
Adverse Effects of Oral Antihistamines
ranking in order of most sedating to least
Drowsy & performane impairment
- HA
- loss of appetite
- N/V
- epigastric distress
anticholenergic effects
- dry mouth
- urinary retention
- constipation
- CV effects
Ranking
Most sedation = diphenhydramine
cholrpheniramine
minimally = cetirizine, levocitirazine
least = fexofenidine, loratadine
some antihistmianes come in opthalmic forms – which
Opthalmic = only controllong the eye symptoms
- olopatadine
- azelastine
- ketofien
intranasal formualtions also avalible
