Actions and Spectrum: 

diphenhydramine, an antihistamine, is used to treat allergy symptoms like scratchy throat, runny nose, and watery eyes. It functions by inhibiting the effects of histamine, a chemical the body releases in reaction to allergens. In addition to its ability to cure insomnia. diphenhydramine also possesses calming qualities that make it a moderate tranquillizer. 

The nonsteroidal anti-inflammatory medicine (NSAID) ibuprofen, on the other hand, is used to treat inflammation, fever, and discomfort. It functions by preventing the body from producing prostaglandins, which are chemicals released in reaction to damage or inflammation. ibuprofen is frequently used to treat ailments including arthritis, menstrual cramps, headaches, and toothaches. 

DRUG INTERACTION

Contraindicated  

Serious Use Alternative  

Monitor Closely  

Minor  

Frequency not defined  

For ibuprofen 

Rash 

Vomiting 

Edema 

Tinnitus 

Nausea 

Epigastric pain 

For diphenhydramine 

Confusion 

Xerostomia 

Pharyngeal and nasal mucosa dryness 

Sedation 

May decrease cognitive function in geriatric patients 

Thick sputum 

Anticholinergic effects 

Black Box Warning 

For its sedative effects, diphenhydramine may include a black box warning, especially in older persons. It may make you feel confused or lightheaded and raise your chance of falling. Also, people with asthma or other respiratory disorders should take caution when using diphenhydramine since it has the potential to cause respiratory depression. 

For its elevated risk of cardiovascular events including heart attack and stroke, ibuprofen may have a black box warning. Those who already have cardiovascular disease are more at risk for this, and long-term ibuprofen usage may make the risk worse. 

Contraindication/Caution: 

Contraindication: 

• known intolerance or allergy to ibuprofen, diphenhydramine, or any of the medication’s ingredients 
• prior usage of diphenhydramine and bronchospasm or other respiratory problems 
• Gastrointestinal bleeding or ulceration that is present or recent. 
• serious renal or liver illness 
• breastfeeding or pregnancy 

Caution: 

• asthma or other respiratory disorders in the past 
• with stomach bleeding or ulcers 
• cardiovascular disease risk factors such high blood pressure, high cholesterol, or smoking, or a history of cardiovascular illness 
• use of sedatives such as alcohol or other drugs that might intensify the sedative effects of diphenhydramine 

Pregnancy warnings:     

Pregnancy category: NA 

Lactation: Excretion into human milk is known 

Pregnancy Categories:         

Category A: Studies that were well-controlled and met expectations revealed no risk to the fetus in either the first or second trimester. 

Category B: There were lack of studies on pregnant women and no evidence of risk to the foetus in animal experiments.   

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 available 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: There is no data available for the drug under this category

Pharmacology 

diphenhydramine is an antihistamine that works by inhibiting the effects of histamine, a chemical that the body releases in reaction to allergens. diphenhydramine helps to reduce allergy symptoms such itchiness, sneezing, runny nose, and watery eyes by inhibiting the activity of histamine. 

ibuprofen is a nonsteroidal anti-inflammatory medicine (NSAID) that reduces pain and inflammation by inhibiting the body’s ability to make prostaglandins, which are chemicals that are created in reaction to injury or inflammation. ibuprofen aids in reducing inflammation, fever, and discomfort by preventing the formation of prostaglandins. 

Pharmacodynamics 

As a competitive antagonist of histamine H1 receptors, diphenhydramine prevents histamine from binding to these receptors. diphenhydramine may pass the blood-brain barrier and bind to histamine H1 receptors in the brain, which may explain its sedative effects. 

The prostaglandin-producing enzyme cyclooxygenase (COX) is non-selectively inhibited by the anti-inflammatory drug ibuprofen. It decreases the formation of prostaglandins, which cause pain, fever, and inflammation, by inhibiting COX. Inhibiting platelet aggregation, which raises the risk of bleeding, is another way that ibuprofen is known to act. 

Pharmacokinetics 

Absorption   

After oral treatment, diphenhydramine is quickly absorbed, reaching peak plasma concentrations in within two hours. Taking it with meals might slow down the absorption. ibuprofen is similarly quickly absorbed when taken orally, reaching peak plasma concentrations in within one to two hours. 

Distribution 

ibuprofen and diphenhydramine are both strongly protein-bound drugs (about 98%), which implies that they bind to blood proteins and are not readily absorbed by tissues. They both have a distribution volume of around 1 L/kg. 

Metabolism 

The primary metabolite of diphenhydramine is N-demethylated diphenhydramine, which is produced by the liver’s cytochrome P450 (CYP) system. ibuprofen is metabolized by the liver via glucuronidation and oxidation, with ibuprofen glucuronide being the main byproduct. 

Elimination and excretion 

Both diphenhydramine and ibuprofen are largely excreted through the kidneys, with diphenhydramine being eliminated in the urine as a drug and metabolites that have not been altered, and ibuprofen being eliminated in the urine as a drug and metabolites that have not been altered. diphenhydramine has an elimination half-life of around 4 hours, whereas ibuprofen has an elimination half-life of about 2-4 hours. 

Administration:  

Products containing both ibuprofen and diphenhydramine are often sold as oral tablets or capsules. 

Depending on the drug and the disease being treated, the frequency and interval of dose might also change. 

Patient information leaflet 

Generic Name: diphenhydramine/ibuprofen 

Why do we use diphenhydramine/ibuprofen? 

Products containing both diphenhydramine and ibuprofen are frequently used to treat pain as well as symptoms of colds, the flu, and allergies. 

The medication’s diphenhydramine component is an antihistamine that can aid with cold and allergy-related symptoms like runny nose, sneezing, and itching. Moreover, it can aid in easing the effects of sleeplessness and motion sickness.  

The medicine contains ibuprofen, a nonsteroidal anti-inflammatory drug (NSAID) that can be used to treat inflammation and mild to moderate discomfort. It is frequently used to treat toothaches, muscular pains, menstrual cramps, headaches, and menopausal symptoms.