PHCT Flashcards
- Found in many over-the-counter cough and cold
preparations - Often found in combination products containing
antihistamines, decongestants, or acetaminophen.
Dextromethorphan
Examples of Dextromethorphan
Nyquil, Robitussin DM, Triaminic DM, and Vick
Pediatric Formula 44
a synthetic analogue of codeine
d-isomer of 3-methoxy-N-methylmorphinan
– Has no apparent analgesic or addictive properties and produces relatively mild opioid effects in overdose.
– Also has anticholinergic properties
Dextromethorphan
Dextromethorphan | Well-absorbed orally, and effects are apparent within ______
15-30 minutes
Dextromethorphan | duration of effect is normally ____
3-6 hours
Both dextromethorphan and its o-demethylated
metabolite appear to antagonize
N-methyl-D-aspartate (NMDA) glutamate receptors.
inhibits reuptake of serotonin,
and may lead to the serotonin syndrome in patients
taking monoamine oxidase inhibitors
Dextromethorphan
Dextromethorphan | Toxic Dose
10mg/kg
Dextromethorphan | Usual recommended adult daily dose of dextromethorphan is
; in children age 2-5 years, up to 30 mg/d.
60-120 mg/d
Dextromethorphan | Usual recommended
in children age 2-5 years
up to 30 mg/d
Dextromethorphan | Clinical Presentation
* Clumsiness
* Ataxia
* Nystagmus
* Restlessness
* Visual and auditory hallucinations
Mild intoxication
Dextromethorphan | Clinical Presentation
- Stupor
– Coma
– Respiratory depression (coingestion with alcohol)
– Pupils may be dilated or constricted.
– Seizures are reported after ingestions of 20-30 mg/kg
Severe Poision
Dextromethorphan | Clinical Presentation
– Severe hyperthermia
– Muscle rigidity
– Hypertension
– Related to serotonin syndrome.
Therapeutic doses taking MAOI
Dextromethorphan | Treatment
Drug , mg
Naloxone ; 0.06 - 0.4mg
Dextromethorphan | Treatment
Opioid Intoxication
0.4-2 mg naloxone IV
Dextromethorphan | Treatment
Decontamination:
Activated Charcoal
PPA means
Phenylpropanolamine
- Also widely used as an appetite
suppressant - Widely available in nonprescription nasal decongestants and
cold preparations - Usually also contain antihistamines and cough suppressants
Phenylpropanolamine (PPA)
PPA example (3)
- Phenylephrine
- Ephedrine
- Pseudoephedrine
PPA
Mechanism of PPA + Phenylephrine
- Direct alpha-adrenergic agonists
- PPA produces mild β1-adrenergic stimulation and acts in part indirectly by enhancing norepinephrine release
PPA
Ephedrine and pseudoephedrine
- Have both direct and indirect alpha- and beta-adrenergic activity
- They clinically produce more beta-adrenergic
stimulation than PPA or phenylephrine
PPA, phenylephrine, and ephedrine have _____ (low, high) toxic:therapeutic ratios
LOW
PPA | Toxicity often occur after ingestion of just _____ times the therapeutic
dose
2-3x
PPA |
_____ is slightly less toxic, with symptoms occurring after 4- 5 times the usual therapeutic dose
Pseudoephedrine
PPA
HTN is treated if diastolic pressure is higher than
100-105mmHg
PPA |
TX for HTN ; Non-pharmacological
phentolamine or nitroprusside;
upright position
PPA |
Caution in TX of HTN
Do not use beta blockers alone w/o first giving a
______.
vasodilator
PPA |
Tx for Arrhythmias
Give propanolol or esmolol
PPA |
Caution:
Do not treat AV block or sinus bradycardia
associated with hypertension
PPA |
Treatments
1.) Ipecac-induced emesis may be useful for initial treatment.
2.) Administer activated charcoal and cathartic.
PPA |
widely used for the treatment of asthma
Methylxanthine
IV infusions of ______ are used to treat
bronchospasm, congestive heart failure and neonatal
apnea.
aminophylline
Commonly used orally in sustained-release preparations
Theophylline
Theophylline |
Toxic Dose:
Acute single dose of _____
8-10 mg/kg
Theophylline |
Acute oral overdose of more than _____ may
potentially result in a level above 100 mg/L and
significant toxicity.
50 mg/kg
Theophylline |
Status epilepticus, , seizures (serum levels)
> 100 mg/L
Theophylline | When excessive doses are administered repeatedly
over 24hours or longer
Chronic Intoxication
Theophylline |
Drugs Examples
Use low-dose ______ 0.01-0.03 mg/kg IV
propanolol
Theophylline |
Drugs Examples
_______ 25-50 µg/kg/min
Esmolol
Bronchodilators-_____ agonists
B2
Bronchodilators:
first line in the tx of acute
exacerbation of BA
primary reliever medication
Short acting rapid onset
Bronchodilators:
prophylactic agent (acute attacks)
for controlling nocturnal attacks
controller medication
Long acting slow onset
Bronchodilators:
controller usually given through inhalation
Long acting with rapid onset
Selective B2 agonists
Oral, MDI
Albuterol, Metaproterenol
Selective B2 agonists
For severe asthma;
SC inj.(0.25 mg)
Terbutaline
Selective B2 agonists
long-acting
DOA: 12 hours
Salmeterol &
Formoterol
Type of Bronchodilators reserved for special situations (cardiac stimulation)
Bronchodilators – Non-selective
Non-Selective | Bronchodilator
Epinephrine
Dose:
Onset:
Duration:
Epinephrine
SC (0.4 mL of 1:1000 solution) inhaled - 320 g per puff
Onset: 15 minutes
Duration: 60–90 mins
Non-Selective | Bronchodilator
Ephedrine
Lower Potency
Non-Selective | Bronchodilator
Inhaled: 80–120 g
Onset: 5 minutes
Duration: 60–90 mins
Isoproterenol
IPRATROPIUM
TIOTROPIUM
Classification:
Anticholinergic/Antimuscarinic
Bronchodilators |
quaternary ammonium derivative of atropine
ipratropium bromide
Bronchodilators |
longer-acting selective antimuscarinic agent
tiotropium
Bronchodilators |
Also used in allergic
rhinoconjunctivitis
Mast cell stabilizers
