Respiratory, Antihistaminic and GI Drugs

Question 1

Conditions causing decreased O2 tension in the blood

Answer 1

Obstructive disorders
Decreased breathing
Cardiovascular conditions (Decreased contact surface area, increased diffusion distance, inconsistent lung aeration, and inconsistent lung circulation)

Question 2

Respiratory stimulants/analeptics

Caffeine, doxapram

Answer 2

Indicated for: Drug overdose, decreased recovery time from anesthesia, and sleep apnea in infants
MOA: Mostly unknown, but some act on the medulla
Cautions: May potentiate depressant effects

Question 3

Airway Remodeling

Answer 3

Permanent, negative changes to the respiratory system that may occur due to chronic irritation of the bronchioles. Increased collagen deposition, bulking of the airway smooth muscles, mast cell/goblet cell hyperplasia, and epithelial cell hypertrophy

Question 4

Sympathomimetics

Albuterol, Epinephrine

Answer 4

Indicated for: Rescue drug for asthma, or other cases of COPD
MOA: Beta 2 agonist, relaxes smooth muscles of bronchioles. Often given through inhalation, or may be injected or given orally
Cautions: May cause tachycardia, palpitations, hypertension, nausea, vomiting, headache, and dizziness. Tolerance possible

Question 5

Xanthines

Aminophylline/Theophylline

Answer 5

Indicated for: Asthma and pulmonary edema
MOA: Phosphodiesterase inhibitor which acts as a smooth muscle relaxant
Cautions: Gastric irritation, nausea, vomiting (acts directly on emetic center), retlessness, anxiety, convulsion, hypotension, headache
Usually given orally, may be given as IV bolus in emergencies

Question 6

Anticholinergic

Ipratropium (Atrovent)

Answer 6

Indicated for: COPD (not asthma)
MOA: Inhibit cholinergic effects, preventing bronchoconstriction (simple bronchodilator)
Cautions: Drying effect, may aggravate asthma

Question 7

Asthma Prophylactic/Mast Cell Stabilizers

Cromolyn

Answer 7

Indicated for: Asthma attack prevention (especially exercise-induced asthma)
MOA: Anti-inflammatory, prevents the release of histamine without cardiac stimulation
Cautions: May cause bronchospasm, throat irritation, headache, bitter taste.
Takes 2 weeks and 4 - 6 doses per day to become effective
Good especially for older patients

Question 8

Leukotriene Receptor Antagonists

Answer 8

Indicated for: Asthma attack prevention, allergic rhinitis
MOA: Prevents leukotrienes from causing inflammation by blocking receptors
Caution: Heacache, GI upset, inhibits cytochrome P450 system so other drugs are metabolized more slowly

Question 9

Corticosteroids

Dexamethasone

Answer 9

Indicated for: Conditions not managed by other medications. Asthma, COPD, status asthmaticus
MOA: Suppression of antibody formation, increase of cAMP for promoting bronchodilation, decrease of cGMP for decreasing bronchoconstriction
Local side effects: Hoarseness, dry mouth, local mouth/pharynx infections
Systemic side effects: Irreversible osteoporosis, cataracts, and growth stunting in children, reversible immunosuppression, salt/water retention, restlessness, insomnia, possible depression
Caution: Must be withdrawn slowly. Patient may need additional glucocorticoid during times of stress

Question 10

Narcotic Antitussives

Codeine

Answer 10

Indicated for: Painful, exhausting, nonproductive cough
MOA: Suppresses cough center in medulla
Cautions: Potential for abuse, constipation, and respiratory depression
Use only if not managed with nonnarcotic antitussives
BEST TO TREAT CAUSE OF COUGH

Question 11

Nonnarcotic Antitussives

Dextromethorphan

Answer 11

Indicated for: Painful, exhausting, nonproductive cough
MOA: Reduce activity of lung stretch receptors, or suppress cough center in medulla without analgesic/addictive properties (dextromethorphan)
Side effects not a concern if cough is severe enough to require this med
BEST TO TREAT CAUSE OF COUGH

Question 12

Demulcents

Gargles, lozenges, syrups, steam treatment

Answer 12

Indicated for: Cough and throat irritation

MOA: Protects respiratory lining from irritation and contact with air

Question 13

Expectorants

Answer 13

Indicated for: Asthma, COPD, bronchitis, pneumonia, coughs

MOA: Gastric irritants, make secretions more fluid so that irritants can be moved

Question 14

Drugs which affect mucus

Answer 14

Mucolytic agents (enzymes
Acetylcysteine
Surface active drugs
Diluents (water, saline)
Dprnase Alfa (DNAase, used for cystic fibrosis)

Question 15

Adrenergic agents

Answer 15

Indicated for: Nasal congestion from colds and allergies
MOA: Nasal vasoconstriction
Caution: Causes habituation

Question 16

Intranasal steroids

Answer 16

Indicated for: Allergies

May increase risk of thrush, prevent healing of damaged nasal mucosa

Question 17

Anithistaminics

Answer 17

Indicated for: allergies, cold symptoms

Question 18

H1 receptors

Answer 18

Cause contraction of bronchial and intestinal smooth muscle and dilation of arterioles and capillaries when stimulated

Question 19

H2 receptors

Answer 19

Cause increased gastric secretion when stimulated

Question 20

H1 Antagonists

Chlorpheniramine, Cwetirizine, Meclizine

Answer 20

Indicated for: Prevention of allergic reaction, motion sickness
MOA: Prevents binding of stimulants to H1 receptors, depress CNS and decrease sensitivity of inner ear
Side effects: Drowsiness, sedation, dizziness, agitation, hallucination (first generation), dry mouth, blurred vision
Caution: Potentiate other sedative-hypnotics, asthma, blood dyscrasias

Question 21

H2 Antagonists

Famotidine, Rantidine

Answer 21

Indicated for: Decrease gastric secretions to allow healing of ulcers, treat heartburn
MOA: Decrease gastric secretions
Side effects: Sometimes dizziness, diarrhea, muscle pain, rash, breast enlargement in some men, mental confusion in older patients
INHIBITS CP450, DECREASES DRUG METABOLISM

Question 22

Systemic Antacids

Sodium Bicarbonate

Answer 22

Indicated for: Peptic ulcer, heartburn
MOA: Decrease stomach pH
May cause: Systemic alkylosis and electrolyte imbalance
Alters absorption of other drugs

Question 23

Ninsystemic antacids

Aluminum, calcium, and magnesium compounds

Answer 23

Indicated for: Peptic ulcer, heartburn
May cause: constipation or diarrhea
Alters absorption of other drugs

Question 24

Sedative/Antisecretory Agents

Answer 24

H2 Antagonists (inhibit gastric secretion)
Anticholinergic drugs
Prostaglandins (Reduce acid, increase mucus secretion; contraindicated in pregnancy due to possible miscarriage)
Proton Pump Inhibitors (Suppresses acid secretion, ma cause alkalinization

Question 25

Cisapride, Metoclopramide

Answer 25

Indicated for: Heartburn, nausea caused by gaseous distension
MOA: Relaxes pylorus, stimulate motility to increase gastric emptying
Increases sensitivity to acetylcholine

Question 26

Sucralfate

Answer 26

Indicated for: Ulcers

MOA: Adheres to ulcerated region to protect it, decreases pepsin activity

Question 27

Modern Ulcer Therapy

Answer 27

1) Antisecretory agent (H2 agonist or proton pump inhibitor)
2) Bismuth to damage bacterial cell walls and decrease bacterial adherence to mucosal cells
3) At least 2 antibiotics to avoid H. pylori resistance

Question 28

Digestants

Answer 28

Acids and enzymes

No longer considered effective, except for pancreatic enzymes

Question 29

Emetics

Answer 29

Indicated for: Poisoning
Caution: Vomiting contraindicated with some poisons, may induce convulsions if taking convulsant, oil-based substances could be aspirated into lungs, corrosive substances may damage mouth, throat and esophagus

Question 30

Local Antiemetic

Antacid Carminative

Answer 30

Indicated for: Vomiting

MOA: Relieves irritation

Question 31

Systemic Antiemetic

Answer 31

Phenothiazenes (most effective)
Antihistamines (for motion sickness)
Tetrahydrocannabinol/THC (often used for chemotherapy-induced nausea, but may cause drowsiness, dry mouth, tachycardia, dizziness, inability to concentrate, disorientation, anxiety, depression, paranoia, manic psychosis, and visual hallucinations)
Metoclopramide (Relieves heartburn and nausea caused by gaseous distension)

Question 32

Cathartics

Answer 32

Indicated for: Constipation and necessary elimination
for surgery, diagnostic procedures, worm infestations, and chemical poisoning
MOA: Irritants stimulate peristalsis, bulk-forming drugs attract water to lubricate feces, saline attracts water, and lubricants/fecal moistening agents keep feces soft
Contraindicated for: Undiagnosed abdominal pain, GI obstruction, and later stages of pregnancy

Question 33

Antidiarrheics

Answer 33

Demulcents (prevent irritation)
Absorbents (absorb gas or irritating substance)
Astringents (Prevent irritation by precipitating protein and covering membrane surface
Antiinfectives (Subdue microorganisms)
Sedatives/antispasmodics

Question 34

Carminatives

Answer 34

Indicated for: Gas expulsion

Caution: Absorbs oral medications

Question 35

Barium sulfate

Answer 35

Indicated for: Contrast media for diagnostics

Poisonous but insoluble

Question 36

Organic iodine compounds

Answer 36

Indicated for: Contrast media for diagnostics

Cautions: Renal disease, hepatic disease, iodine allergy, and any allergy indicated histamine sensitivity