Sudafed 12 hour and Allegra allergy drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Sudafed 12 hour (pseudoephedrine hydrochloride) and Allegra allergy (fexofenadine hydrochloride). Common drug interactions include drug hypersensitivity among females and contusion among males.

The phase IV clinical study analyzes what interactions people have when they take Sudafed 12 hour and Allegra allergy. It is created by eHealthMe based on reports of 16 people who take the same drugs from the FDA, and is updated regularly.

What is Sudafed 12 hour?

Sudafed 12 hour has active ingredients of pseudoephedrine hydrochloride. It is often used in nasal congestion. eHealthMe is studying from 4,687 Sudafed 12 hour users. Check the latest studies of Sudafed 12 hour.

What is Allegra allergy?

Allegra allergy has active ingredients of fexofenadine hydrochloride. It is often used in allergies. eHealthMe is studying from 13,594 Allegra allergy users. Check the latest studies of Allegra allergy.

eHealthMe: drug outcomes in the real world

eHealthMe runs one of the largest post-marketing drug safety studies in the world. We study millions of patients and 5,000 more each day. Our data-driven phase IV clinical trials have been referenced on 800+ peer-reviewed medical publications including The Lancet, Mayo Clinic Proceedings, and Nature. Tools to study our phase IV findings are available to the public, anonymous and free >>>.

On Sep, 01, 2026

16 people who take Sudafed 12 hour and Allegra allergy together, and have interactions are studied.

Sudafed 12 hour and Allegra allergy drug interactions.

What are the common drug interactions of Sudafed 12 Hour and Allegra Allergy, by gender? *:

female:

Drug hypersensitivity
Fatigue (feeling of tiredness)
Fungal infection
Hallucination (an experience involving the perception of something not present)
Headache (pain in head)
Pain
Peripheral swelling
Rheumatoid arthritis (a chronic progressive disease causing inflammation in the joints)
Skin irritation
Suicidal ideation

male:

Contusion (a type of hematoma of tissue in which capillaries)
Nephrolithiasis (calculi in the kidneys)
Somnolence (a state of near-sleep, a strong desire for sleep)
Eye pain
Sleep apnoea syndrome (a sleep-related disorder in which the effort to breathe is diminished or absent)

What are the common drug interactions of Sudafed 12 Hour and Allegra Allergy, by age (0-1 to 60+)? *:

0-1:

n/a

2-9:

n/a

10-19:

n/a

20-29:

n/a

30-39:

Anxiety
Contusion (a type of hematoma of tissue in which capillaries)
Crying
Depression
Drug hypersensitivity
Fatigue (feeling of tiredness)
Hallucination (an experience involving the perception of something not present)
Nephrolithiasis (calculi in the kidneys)
Somnolence (a state of near-sleep, a strong desire for sleep)
Suicidal ideation

40-49:

Rheumatoid arthritis (a chronic progressive disease causing inflammation in the joints)
Skin discomfort (skin pain/irritation)
Skin irritation
Sleep apnoea syndrome (a sleep-related disorder in which the effort to breathe is diminished or absent)
Sleep disorder
Urinary tract infection
Weight increased
Rash
Dermatitis atopic (inflammatory, chronically relapsing, non-contagious and pruritic skin disorder)
Discomfort

50-59:

n/a

60+:

Hangover
Peripheral swelling

What are the existing conditions these people have? *

Narcolepsy (brain's inability to regulate sleep-wake cycles normally): 7 people, 43.75%
Dermatitis Atopic (inflammatory, chronically relapsing, non-contagious and pruritic skin disorder): 3 people, 18.75%
Cataplexy (loss of muscle tone accompanied by full conscious awareness): 3 people, 18.75%
Rheumatoid Arthritis (a chronic progressive disease causing inflammation in the joints): 2 people, 12.50%
Psoriasis (immune-mediated disease that affects the skin): 2 people, 12.50%
Restless Leg Syndrome (a powerful urge to move your legs): 1 person, 6.25%
Peripheral Swelling: 1 person, 6.25%
Neurotrophic Keratopathy (decreased corneal sensitivity and poor corneal healing): 1 person, 6.25%
Migraine (headache): 1 person, 6.25%
Ill-Defined Disorder: 1 person, 6.25%

* Approximation only. Some reports may have incomplete information.

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