Pharmacologic Therapy - Respiratory Disorders

Question 1

histamine

Answer 1

a major inflammatory mediator in ALLERGIC DISORDERS
often activated in these conditions:

• allergic rhinitis (hay fever, mold, dust)
• anaphylaxis
• angioedema
• drug fevers
• insect bites
• urticaria

Question 2

what are ANTIHISTAMINES?

Answer 2

drugs that directly compete with HISTAMINE for specific receptor sites
- also known as HISTAMINE ANTAGONISTS

Question 3

what are the properties of antihistamines?

Answer 3

• antihistaminic
• anticholinergic
• sedative

Question 4

what are our TWO types of HISTAMINE RECEPTORS?

Answer 4

• H1 (histamine 1)
  work mainly by conducting SM contraction & dilation of capillaries
• H2 (histamine 2)
  works mainly in the GI system; accelerates HR + secretes gastric acid

Question 5

H1 antagonists

Answer 5

• work by blocking our H1 receptors
• mainly known as our “antihistamines”
• has primarily ANTICHOLINERGIC EFFECTS

examples:
chlorpheniramine, fexofenadine (Allegra), loratadine (Claritin), cetirizine (Zyrtec), diphenhydramine (Benadryl)

Question 6

H2 blockers

Answer 6

• blocks our H2 receptors
• mainly used for acid-control / helps to REDUCE gastric acid in PUD

examples:
cimetidine (Tagamet), famotidine (Pepcid), nizatidine (Axid)

Question 7

MOA of antihistamines

Answer 7

• work by blocking and competing with HISTAMINE at the receptor sites
• **does NOT PUSH HISTAMINE OUT; simply just competes
• prevents adverse effects of histamine stimulations
• works much better if used earlier in histamine-mediated reactions

Question 8

what are some ADVERSE REACTIONS when histamine is stimulated?

Answer 8

• think of severe allergic reactions!
• capillary permeability increases = increased BP/itchiness
• increased gastric secretions/secretions everywhere (saliva, lacrimal, bronchial etc…)
• increased HR
• SM constriction (difficulty breathing/blood flow/flushing)

**antihistamines work by REVERSING these effects
- decreases cap permeability by dilation
- decreases HR
- drying effects; decreases secretions
- sedative effect

Question 9

antihistamine indications

Answer 9

• nasal allergies
• seasonal/perennial allergic rhinitis
• allergic reactions
• motion sickness
• parkinson’s dz
• sleep disorders
• common cold symptoms

**antihistamines do NOT CURE/KILL causative organism (curative), they just RELIEVE (palliative) symptoms

Question 10

antihistamine contraindications

Answer 10

• drug allergy
• narrow-angle glaucoma
• cardiac disease/HT
• kidney disease
• asthma/COPD (do not use as SOLE DRUG THERAPY during acute asthma attacks **use epipen/albuterol)
• PUD
• seizure disorders
• BPH
• pregnancy

Question 11

antihistamines adverse effects

Answer 11

drying effects **most common - ANTICHOLINERGIC EFFECTS
- dry mouth
- diff. urination
- constipation
- vision changes
- drowsiness (mild to deep sleep)

Question 12

describe the difference between NON-SEDATING ANTIHISTAMINES vs. SEDATING HISTAMINES

Answer 12

NON-SEDATING HISTAMINES:

• developed to remove common side effect of sedation
• works more PERIPHERALLY, meaning they DO NOT cross the BBB/fewer CNS effects
• longer duration of action *can be taken once a day/has increased compliance rates

SEDATING-HISTAMINES:

• more older/original drugs
• works both CENTRALLY & PERIPHERALLY to block histamine; they cause sedation; however are often more effective in results

Question 13

what are our NON-SEDATING ANTIHISTAMINES?

Answer 13

• fexofenadine (Allegra)
• loratadine (Claritin)
• cetirizine (Zyrtec)

Question 14

loratadine

Answer 14

• taken typically once a day (tab/syrup form + taken in combo with decongestant - PSEUDOEPHEDRINE)
• relieves seasonal allergic rhinitis/itching
• pregnancy category B drug

Question 15

what medications/drugs should NOT be given with LORATADINE?

Answer 15

• aclidinium
• azelastine
• ipratropium
• orphenadrine
• potassium chloride
• tiotropium
• umeclidinium

Question 16

what are our traditional/SEDATING HISTAMINES?

Answer 16

• diphenhydramine
• brompheniramine
• chlorpheniramine
• dimenhydrinate
• meclizine
• promethazine

Question 17

diphenhydramine

Answer 17

• avab. ORAL/PARENT/TOPICAL
• sedating/traditional
• also used as a hypnotic due to sedating effects
• XX older adults - creates a “hangover effect”
• used to relieve allergies, motion sickness, parkinsons, promote sleep
  [*also used with epinephrine to manage anaphylaxis in ACUTE dystonic reactions]
• pregnancy cat. B

Question 18

what are the THREE MAIN TYPES of decongestants?

Answer 18

• ADRENERGIC
  is the largest group; aka sympathomimetics
• ANTICHOLINERGIC
  less common; aka parasypatholytic
• CORTICOSTEROIDS
  are topical; intranasal steroids

Question 19

MOA decongestants

Answer 19

• shrinks engorged nasal MM
• relieves nasal stuffiness
  ADRENERGIC DRUGS - work by constricting small arterioles in the URI/nasal sinuses
  NASAL STEROIDS - reduce inflammatory response by the organisms/creates an anti-inflammatory effect

Question 20

decongestants indication

Answer 20

• nasal congestion / acute or chronic rhinitis / sinusitis / hay fever
• reduces swelling of the nares

Question 21

contraindications decongestants *adrenergic drugs

Answer 21

• drug allergies
  ADRENERGIC DRUGS:
• narrow-angle glaucoma
• uncontrolled cardio dz
• HT
• DM
• hyperthyroidism

Question 22

decongestants adverse effects

Answer 22

• nervousness
• insomnia
• palpitations
• tremors
• mucosal irritation/dryness (intranasal steroids)
• systemic effects (high doses);
  headaches, HT, nervousness, dizziness, palpations

Question 23

interactions decongestants

Answer 23

• adrenergic drugs + systemic sympathomimetic drugs = drug toxicity
• MAOIS > can increase BP when given with sympathomimetic nasal drugs

Question 24

describe the different ROUTES of the decongestants

Answer 24

ORAL ROUTE

• prolonged effects, delayed onset
• less potent
• no rebound congestion
• mainly seen for adrenergic drugs

TOPICAL ROUTE

• prompt/rapid
• potent
• can cause rebound congestion/exacerbation risk
• topical adrenergic

INHALED INTRANASAL STEROIDS/ANTICHOL

• prophylactic usage for URI patients/symptoms
• X rebound congestion

Question 25

what are some typical OTC decongestants?

Answer 25

- Nasacort AQ (triamcinolone acetonide) - Flonase Allergy Relief (fluticasone propionate) - Rhinocort Allergy Spray (budesonide). *caution with nasal mucosal infections - can depress immunity *drug allergies

Question 26

oxymetazoline / afrin

Answer 26

- sympathomimetic/adren. drug - similar structure to TETRAHYDROZOLINE - dilates arterioles to constrict > reduces BF and congestion - should not be used more than 3 days at a time (risk of REBOUND CONGESTION)

Question 27

antitussives

Answer 27

- stops cough reflex - used ONLY FOR NONPRODUCTIVE COUGHS - have opioid or non-opioid

Question 28

benzonatate

Answer 28

- type of antitussive drug; is NOT a OPIOID - suppresses cough by NUMBING the STRETCH RECEPTORS in the RESP. TRACT - numbness prevents STIMULATION of the COUGH REFLEX in the MEDULLA - pregnancy C drug

Question 29

benzonatate contraindications

Answer 29

- no known contraindications - cautious with usage with patients with PRODUCTIVE COUGH (antitussives also have opioids for usage - assess for opioid dependency/resp. depression

Question 30

benzonatate adverse effects

Answer 30

- dizziness - headaches - sedation - nausea

Question 31

tuberculosis

Answer 31

medical diagnosis for any infection caused by the bacteria known as Mycobacterium tuberculosis - causes GRANULOMAS in the lungs and accumulations of inflammatory cells

Question 32

what are our FIRST-LINE ANTITUBERCULAR DRUGS?

Answer 32

- INH/ISONIAZID* - RIFAPENTINE - ETHAMBUTOL - RIFABUTIN - PYRAZINAMIDE (PZA) - RIFAMPIN* - STEPTOMYCIN

Question 33

what are our SECOND-LINE DRUGS?

Answer 33

- BEDAQUILINE* - CAPREOMYCIN - CYCLOSERINE - LEVOFLOXACIN - ETHIONAMIDS - OFLOXACIN - KANAMYCIN - PARA-AMINOSALICYLIC ACID (PAS)

Question 34

what are the THREE GROUPS of TB DRUGS?

Answer 34

- protein wall synthesis inhibitors (PWSI) - cell wall synthesis inhibitors (CWSI) - other MOA (OMOA)

Question 35

TB drugs depend on what for effectiveness

Answer 35

- have to consider TYPE of TB - dosing - duration of treatment/adherence (at least 6 months for TB treatment) - type of drug combo

Question 36

problems for TB therapy

Answer 36

- drug-resistance (MDR-TB) - drug toxicity - patient non-adherence

Question 37

bedaquiline (sirturo)

Answer 37

- first drug approved to treat MDR-TB - works by inhibiting mycobacterial ATP SYNTHASE - ADVERSE EFFECTS: headaches, chest pain, nausea, QT PROLONGATION (BBW) - interactions: ALCOHOL, MIFEPRISTONE, drugs with risk of QT PROLONGATION - administer with FOOD [new drug for MDR-TB; PRETOMANID]

Question 38

isoniazid/INH

Answer 38

- the DRUG OF CHOICE for TB - metabolized in the liver via ACETYLATION; not everyone has the gene for this metabolism--causing a "slow acetylator"--have to adjust dosing - can be solo or used in combo - ADV EFFECTS: LIVER DZ, PERIPHERAL NEURO, HEPATOTOXICITY/PYRIDOXINE DEFICIENCY - may need to take vitamin supplements

Question 39

rifampin / rifabutin / rifapentine

Answer 39

- used to treat infections by NON-TB MYCOBACTERIAL SPECIES - ADV EFFECTS: SECRETIONS (URINE, FECES, SALIVA,SKIN, SWEAT > RED-ORANGE-BROWN COLOR and HEPATITIS - oral

Question 40

TB therapy patient ed

Answer 40

- remember--TB is spread via AIRBORNE DROPLETS: via human, animal etc../coughing or sneezing - therapy can last 6 - 12 months - very important to have strict adherence - can be CONTAGIOUS during the initial period of illness - no alcohol