Antihistamines, Decongestants, Antitussives, and Expectorants Flashcards
what are Antihistamines drugs?
Drugs that reduce the physiological effects of histamine
What are Decongestants?
Drugs that reduce congestion/swelling mainly in the upper and lower respiratory tract
What are Antitussive Drugs?
Drugs that reduce coughing in the body
What are Expectorants drugs?
Drugs that aid in the coughing up and spitting out of excessive mucus that has built up in the body (Respiratory tract); drugs that make you cough
What is Empirical therapy?
Treating the most likely cause based on observations and experience
What is Histamine?
A substance that is involved in: Nerve impulse transmission, Dilates capillaries, contraction of smooth muscle, stimulates gastric secretions, increases HR
What are H1 Receptors?
Histamine Receptors that mediate smooth muscle contraction + capillary dilatation.
What are H2 receptors?
Histamine receptors that mediate HR acceleration + gastric secretions +
What is the MOA of Antihistamines?
They bind to basophils and mast cells and block histamine form binding to these cells which prevents the further secretion and effects of histamine (swelling, smooth muscle contraction (lungs and stomach), capillary dilation (decreased BP and edema))
Indications of Antihistamines?
Managing nasal allergy symptoms, common cold symptoms, allergic reactions, vertigo, motion sickness, PD
Contraindications of Antihistamines?
Sole use of asthma attack due to drying effect and risk of mucus plug, glaucoma, pregnancy, COPD, seizures, Heart/kidney disease,
What is the chief side effects of antihistamines?
Drowsiness, dry mouth, constipation, change in vision
Name Antihistamine drugs , and their class, you need to know for the Final Exam
- Loratadine nonsedating 2. Diphenhydramine traditional
What is the difference between Nonsedating & Traditional Antihistamines?
Nonsedating antihistamines work in the peripheral of the body to block the effects of histamine, do not easily cross the BBB, have a longer DoA
Traditional Antihistamines work in the peripheral and central of the body, have anticholinergic properties, cause sedation, may be more effective than nonsedating drugs.
Pharmacokinetics of Nonsedating Antihistamines
Route: PO
Onset of Action: 1-3 hrs
Peak: 8-12 hrs
HL: 8-24 hrs
Duration of Action: 24hrs
Pharmacokinetics of Traditional Antihistamines
Route: PO
Onset of Action: 15-30 mins
Peak: 2hrs
HL: 7-12 hrs
Duration of Action: 10-12 hrs
What is the MoA of Decongestants?
Decongestants use an adrenergic approach where they constrict small arterioles which makes it easier for mucus to drain from the body internally or externally
OR
A Nasal steroid approach which targets the bodies inflammatory response by “turning off” cells the cause the inflammatory response.
What are the Indications of Decongestants?
Acute or chronic Rhinitis, sinusitis, allergies, reducing swelling in the nasal cavity
Contraindications of Decongestants?
allergy, glaucoma, uncontrolled cardiovascular disease, hypertension, diabetes, hyperthyroidism, prostatitis, when patient is unable to close eyes, hx of stoke, BPH
Adverse effects of Decongestants?
Nervousness, insomnia, palpitations, tremors, mucosal irritation, headache, dizziness, dry mouth change in vison
Name the Decongestant Drugs you need to know for the Exam and their Class
Adrenergic: Pseudoephedrine, Oxymetazoline hydrochloride
Anticholinergics: Ipratropium
Corticoid Steroids: fluticasone, Beclomethasone, budesonide
what are the pharmacokinetics of Decongestants?
Route: Intranasal
On set of Action: 5-10 min
Peak: ?
HL: ?
Duration of Action: 12 hrs
What is the MoA of Antitussives?
Act directly on the medulla (cough center) to suppress the cough reflex
Opioids: provide analgesia, and have a drying effect on the respiratory system (increases mucus viscosity)
What are the indications of Antitussives?
Primary used to stop a nonproductive cough
What are the contraindications of Antitussives?
hart and vessel disease, alcohol use, liver and kidney disease, glaucoma, hypertnesion
What are the adverse effects of Antitussives?
nausea, vomiting, lightheadedness, constipation, drowsiness, sedation, dry mouth
Name the drugs you need to know for the Exam
Codeine, dextromethorphan
What are the Pharmacokinetics of Codeine?
Route: PO
Onset of Action: 15-30 mins
Peak: 34-45 mins
HL: 2.5-4 hrs
Duration of Action: 4-6 hrs
What are the Pharmacokinetics of Dextromethorphan?
Route: PO
Onset of Action: 15-30 mins
Peak: 2.5 hrs
HL: ?
Duration of Action: 3-6 hrs
What is the MoA of Expectorants
They have two MoAs
1. Reflex stimulation: loosening and thinning of secretions by irritating the GI tract
2. Direct stimulation of secretary glands
what are the indications of Expectorants?
Relief of productive cough, decrease tendency of cough
What are the contraindications of Expectorants?
Guaifenesin is contraindicated for allergies
What are the adverse effects of Expectorants?
may cause nausea, vomiting, GI irritation
Names the Expectorant drugs you need to know for the Exam
Guaifenesin
What are the Pharmacokinetics of Expectorant drugs?
