Dimetapp and Diphen drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Dimetapp (brompheniramine maleate; phenylpropanolamine hydrochloride) and Diphen (diphenhydramine hydrochloride). Common drug interactions include adverse drug reaction among females and infusion related reaction among males.

The phase IV clinical study analyzes what interactions people have when they take Dimetapp and Diphen. It is created by eHealthMe based on reports of 25 people who take the same drugs from the FDA, and is updated regularly.

What is Dimetapp?

Dimetapp has active ingredients of brompheniramine maleate; phenylpropanolamine hydrochloride. It is often used in cough. eHealthMe is studying from 4,740 Dimetapp users. Check the latest studies of Dimetapp.

What is Diphen?

Diphen has active ingredients of diphenhydramine hydrochloride. It is often used in insomnia. eHealthMe is studying from 115,432 Diphen users. Check the latest studies of Diphen.

On Jul, 27, 2026

25 people who take Dimetapp and Diphen together, and have interactions are studied.

What are the common drug interactions of Dimetapp and Diphen, by gender? *:

female:

Adverse drug reaction
Back pain
Bradycardia (abnormally slow heart action)
Cerebrovascular accident (sudden death of some brain cells due to lack of oxygen when the blood flow to the brain is impaired by blockage or rupture)
Chills (felling of cold)
Eczema (patches of skin become rough and inflamed, with itching and bleeding blisters)
Feeling cold
Infection
Lung disorder (lung disease)
Malaise (a feeling of general discomfort or uneasiness)

male:

Infusion related reaction
Sinusitis (inflammation of sinus)
Gastroenteritis norovirus (inflammation of stomach and intestine caused by norovirus infection)
Influenza
Malaise (a feeling of general discomfort or uneasiness)
Nasopharyngitis (inflammation of the nasopharynx)
Nausea (feeling of having an urge to vomit)
Petechiae (a small red or purple spot caused by bleeding into the skin)
Shock (a life-threatening condition with symptoms like low blood pressure, weakness, shallow breathing, cold, clammy skin)
Sneezing

What are the common drug interactions of Dimetapp and Diphen, by age (0-1 to 60+)? *:

0-1:

n/a

2-9:

Croup infectious (a loud cough that resembles the barking of a seal and difficulty breathing can transfer to other)
Erythema (redness of the skin)
Fatigue (feeling of tiredness)
Flushing (the warm, red condition of human skin)
Gastroenteritis norovirus (inflammation of stomach and intestine caused by norovirus infection)
Headache (pain in head)
Influenza
Infusion related reaction
Malaise (a feeling of general discomfort or uneasiness)
Nasopharyngitis (inflammation of the nasopharynx)

10-19:

Conjunctivitis (pink eye)
Gastroenteritis viral (inflammation of stomach and intestine caused by virus infection)

20-29:

n/a

30-39:

Blood pressure increased
Cerebrovascular accident (sudden death of some brain cells due to lack of oxygen when the blood flow to the brain is impaired by blockage or rupture)
Nervousness
Vomiting
Anxiety
Dizziness (excl vertigo)
Headache (pain in head)
Injury
Pain
Weakness

40-49:

Back pain
Chronic kidney disease
Gait disturbance
Nephrogenic anaemia (anaemia due to kidney disease)
Nephropathy (damage to or disease of a kidney)
Pain in extremity
Renal failure (kidney dysfunction)

50-59:

Abdominal pain
Cardiomegaly (increased size of heart than normal)
Cerebrovascular accident (sudden death of some brain cells due to lack of oxygen when the blood flow to the brain is impaired by blockage or rupture)
Chest tightness
Constipation
Head injury
Hypoglossal nerve disorder (twelfth cranial nerve (xii) disorder)
Jaw disorder (jaw disease)
Musculoskeletal disorder (disease of the body's muscles, joints, tendons, ligaments and nerves)
Palpitations (feelings or sensations that your heart is pounding or racing)

60+:

Adverse drug reaction
Back pain
Pneumonia
Pyrexia (fever)
Sinus congestion (blockage of sinus)
Sinusitis (inflammation of sinus)
Upper respiratory tract infection
Bradycardia (abnormally slow heart action)
Chills (felling of cold)
Eczema (patches of skin become rough and inflamed, with itching and bleeding blisters)

What are the existing conditions these people have? *

Immunodeficiency Common Variable: 13 people, 52.00%
Primary Immunodeficiency Syndrome: 4 people, 16.00%
Hypogammaglobulinaemia (an abnormally low concentration of gamma globulin in the blood and increased risk of infection): 3 people, 12.00%
Nasopharyngitis (inflammation of the nasopharynx): 2 people, 8.00%
Hypergammaglobulinaemia (elevated levels of gamma globulin): 2 people, 8.00%

* Approximation only. Some reports may have incomplete information.

Do you take Dimetapp and Diphen?

- Personalize this study to your gender, age, symptoms and drugs
- Predict drug outcomes for up to one year with AI
- Get an AI agent to monitor your drugs continuously