aspirin/chlorpheniramine/dextromethorphan/phenylephrine (Alka-Seltzer Plus Cold and Cough Effervescent)
Classes: Cough/Cold, Non-narcotic Combos; Analgesic/Antihistamine/Antitussive/Decongestant Combos
- Dosing and uses of Alka-Seltzer Plus Cold & Cough Effervescent (aspirin/chlorpheniramine/dextromethorphan/phenylephrine)
- Alka-Seltzer Plus Cold & Cough Effervescent (aspirin/chlorpheniramine/dextromethorphan/phenylephrine) adverse (side) effects
- Warnings
- Pregnancy
- Pharmacology of Alka-Seltzer Plus Cold & Cough Effervescent (aspirin/chlorpheniramine/dextromethorphan/phenylephrine)
Dosing and uses of Alka-Seltzer Plus Cold and Cough Effervescent (aspirin/chlorpheniramine/dextromethorphan/phenylephrine)
Adult dosage forms and strengths
aspirin/chlorpheniramine/dextromethorphan/phenylephrine
effervescent tablet
- 325mg/2mg/10mg/7.8mg
Temporary Relief of Common Cold Cough & Upper Respiratory Symptoms
2 tabs fully dissolved in 4 oz of water q4hr; not to exceed 8 tablets/day
Pediatric dosage forms and strengths
aspirin/chlorpheniramine/dextromethorphan/phenylephrine
effervescent tablet
- 325mg/2mg/10mg/7.8mg
Temporary Relief of Common Cold Cough & Upper Respiratory Symptoms
Alka-Seltzer Plus Cold & Cough Effervescent
- <12 years old: Ask a pediatrician
- >12 years old: 2 tablets fully dissolved in 4 oz of water q4hr; not to exceed 8 tablets/day
Alka-Seltzer Plus Cold and Cough Effervescent (aspirin/chlorpheniramine/dextromethorphan/phenylephrine) adverse (side) effects
Freqency Not Defined
Dysrhythmias
Hypotension
Tachycardia
Agitation
Cerebral edema
Coma
Confusion
Dizziness
Headache
Subdural or intracranial hemorrhage
Lethargy
Hives
Rashes
May potentiate peptic ulcer and cause stomach distress or heartburn
Dyspepsia
GI bleeding
Ulceration & perforation
Nausea
Vomiting
Prolongation of prothrombin time
Palpitations
Sedation
Fatigue
Confusion
Depression
Tremors
Irritability
Insomnia
Euphoria
Hemolytic anemia
Thrombocytopenia
Agranulocytosis
Anorexia
Wheezing
Thickening of bronchial secretions
Warnings
Contraindications
Hypersensitivity
Liver damage
< 2 years of age
Hypoprothrombinemia
Vitamin K deficiency
Bleeding disorders
Asthma
G6PD deficiency
Uncontrolled or severe hypertension
Due to association of aspirin with Reye syndrome, do not use in children (<16 y) with viral infections
Narrow-angle glaucoma
Symptomatic prostate hypertrophy
Bladder-neck obstruction
Stenosing peptic ulcer
Cautions
Aspirin: May cause transient decrease in renal function and aggravate chronic kidney disease; avoid use in patients with severe anemia, with history of blood coagulation defects, or taking anticoagulants
Dextromethorphan: Do not take for persistent or chronic cough associated with smoking, asthma, or emphysema, or if it is accompanied by excessive phlegm unless directed by a healthcare provider; may decrease respiration rate
Chlorpheniramine: May cause significant confusional symptoms; not for administration to premature or full-term neonates
Phenylephrine: Caution in elderly patients, hyperthyroidism, myocardial disease, bradycardia, partial heart block or severe arteriosclerosis
Pregnancy and lactation
Pregnancy category D: avoid during pregnancy, especially during third trimester (risk of premature closure of ductus arteriosus)
Lactation: excreted in breast milk; do not breast feed
Pregnant or breastfeeding patients should seek advice of health professional before using OTC drugs
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Alka-Seltzer Plus Cold and Cough Effervescent (aspirin/chlorpheniramine/dextromethorphan/phenylephrine)
Mechanism of action
Aspirin is a stronger inhibitor of both prostaglandin synthesis and platelet aggregation than other salicylic acid derivatives; acetyl group is responsible for inactivation of cyclooxygenase via acetylation; hydrolyzed rapidly in plasma & elimination follows zero order pharmacokinetics
Aspirin: irreversibly inhibits platelet aggregation by inhibiting platelet cyclooxygenase; this, in turn, inhibits conversion of arachidonic acid to PGI2 (potent vasodilator and inhibitor of platelet activation) and thromboxane A2 (potent vasoconstrictor and platelet aggregate)
Chlorpheniramine: blocks muscle responses in histamine & acts as an antagonism of constrictor effects of histamine on respiratory smooth muscle
Dextromethorphan: cough suppressant that acts centrally on cough center in medulla
Phenylephrine: vasoconstrictor & decongestant that relieves symptoms resulting from irritation of upper respiratory tract tissue; shrinks swollen mucous membranes, reduces nasal congestion and tissue hyperemia
Pharmacokinetics
Aspirin
- Bioavailability: 80-100%
- Onset: 5-30 min (PO); 1-2 hr (PR)
- Duration: 3-6 hr (PO); >7 hr (PR)
- Peak plasma time: 0.25-3 hr (PO); 4-5hr (PR)
- Vd: 0.15-0.2 L/kg
- Protein binding: 90-95%
- Metabolism: Liver (microsomal enzyme system)
- Half-life: 2-3 hr (low dose); 15-30 hr (higher dose)
- Renal clearance: 80-100%
- Excretion: Urine (80-100%)
Chlorpheniramine
- Peak Plasma Time: 2-3 hr
- Peak Plasma Concentration: 7.2 ng/mL
- Distribution (Vd): 4-7 L/kg (children); 6-12 L/kg (adults)
- Metabolism: GI mucosa, liver
- Excretion: Urine
- Half-life : 10-13 hr (children); 14-24 hr (adults)
Dextromethorphan
- Onset: 15-30 min
- Duration: 3-6 hr
- Metabolism: Hepatic P450 enzyme CYP2D6
- Excretion: Urine
- Half-life: 2-4 hr (extensive metabolizers); 24 hr (poor metabolizers)
- Peak plasma time: 2-3 hr
Phenylephrine
- Half-life: 2-3 hr
- Onset: 10-15 min
- Duration: 15 min
- Bioavailability: < 38%
- Excretion: Urine (80-90%)
- Peak plasma time: 0.75-2 hr
- Vd: 26-61 L
- Vdss: 340 L


