acetaminophen/doxylamine/phenylephrine

Action and Spectrum

Actions and Spectrum: 

acetaminophen 

It blocks pain impulses generated peripherally and inhibits prostaglandin generation in the CNS. 

doxylamine blocks the histamine competitively from binding to H1 receptors. 

phenylephrine acts as a decongestant and vasoconstrictor. It collapses the swollen membranes, thereby reducing tissue hyperemia and nasal congestion.

Drug Interaction

Adverse Reaction

Frequency not defined 

Dizziness 

Anxiety 

Nervousness 

Headache 

Restlessness 

Reflex tachycardia 

Hypertension 

Rebound congestion 

Stomach upset 

Constipation 

Tremor 

Dermatologic rash 

Mucus thickening 

Black Box Warning

Black Box Warning: 

None 

Contraindication / Caution

Contraindication/Caution: 

Contraindications 

• Hypersensitivity 
• Hypertension 
• Use of MAO inhibitors 
• Severe liver disease 

Cautions 

• Cardiovascular disease 
• Prostate hypertrophy 
• Glaucoma 
• Pregnancy 
• Lactation 

Pregnancy / Lactation

Pregnancy consideration:  

Take advice from healthcare personnel. 

Breastfeeding warnings: Take advice from the healthcare personnel. 

Pregnancy category: 

Category A: well-controlled and satisfactory studies show no risk to the fetus in the first or later trimester. 

Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.    

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.    

Category N: No data is available for the drug under this category. 

Pharmacology

Pharmacology:  

acetaminophen works primarily as an analgesic (pain reliever) and antipyretic (fever reducer). It is thought to inhibit the production of prostaglandins, substances involved in pain and fever signaling in the body. 

phenylephrine acts as a selective alpha-1 adrenergic receptor agonist. It stimulates the alpha-1 receptors in the blood vessels of the nasal passages, leading to vasoconstriction (narrowing of blood vessels). 

Pharmacodynamics: 

The combination of acetaminophen, doxylamine, and phenylephrine provides a multi-symptom approach to address pain, fever, allergic symptoms, and nasal congestion. acetaminophen reduces pain and fever, doxylamine alleviates allergic symptoms and promotes sleep, and phenylephrine is a decongestant to relieve nasal congestion. 

Pharmacokinetics: 

Absorption 

After oral administration, acetaminophen, doxylamine, and phenylephrine are well absorbed from the gastrointestinal tract. It reaches peak plasma concentrations within 1 to 2 hours. 

Distribution 

doxylamine has a large volume of distribution and can cross the blood-brain barrier, contributing to its sedative effects. It is extensively bound to plasma proteins. 

phenylephrine has a relatively small volume of distribution and does not readily cross the blood-brain barrier. 

Metabolism 

The drug gets metabolized extensively in the liver. 

Elimination and Excretion 

The metabolites are excreted in the urine 

Adminstartion

Administration: 

The combination drug is administered through the oral route. It is provided in the form of capsules. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: acetaminophen/doxylamine/phenylephrine 

Why do we use acetaminophen/doxylamine/phenylephrine?  

acetaminophen/doxylamine/phenylephrine is a nasal decongestant and an analgesic used to relieve respiratory tract congestion, rhinitis, allergic rhinitis, rhinorrhea, headache, sinus pain and sneezing.