Tagamet and Omnicef drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Tagamet (cimetidine) and Omnicef (cefdinir). Common drug interactions include amenorrhoea among females and chest pain among males.

The phase IV clinical study analyzes what interactions people have when they take Tagamet and Omnicef. It is created by eHealthMe based on reports of 15 people who take the same drugs from the FDA, and is updated regularly.

What is Tagamet?

Tagamet has active ingredients of cimetidine. It is often used in gastroesophageal reflux disease. eHealthMe is studying from 9,011 Tagamet users. Check the latest studies of Tagamet.

What is Omnicef?

Omnicef has active ingredients of cefdinir. It is often used in sinusitis. eHealthMe is studying from 2,774 Omnicef users. Check the latest studies of Omnicef.

On Jul, 28, 2026

15 people who take Tagamet and Omnicef together, and have interactions are studied.

What are the common drug interactions of Tagamet and Omnicef, by gender? *:

female:

Amenorrhoea (absence of a menstrual period in a woman of reproductive age)
Amnesia (deficit in memory caused by brain damage, disease, or psychological trauma)
Anaemia (lack of blood)
Blister (small pocket of fluid within the upper layers of the skin caused by forceful rubbing (friction), burning, freezing, chemical exposure)
Breast tenderness
Cellulitis (infection under the skin)
Cervical dysplasia (abnormal changes in the cells on the surface of the cervix)
Convulsion (muscles contract and relax rapidly and repeatedly, resulting in an uncontrolled shaking of the body)
Crying
Cyst (a closed sac)

male:

Chest pain
Decreased appetite
Arthralgia (joint pain)
Asthma
Atrioventricular block first degree (heart block first degree)
Back pain
Balance disorder
Benign bone neoplasm (benign (non-cancerous) tumours of the bone)
Bronchopneumonia (inflammation of the lungs, arising in the bronchi or bronchioles)
Cardiac failure congestive

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

0-1:

n/a

2-9:

Decreased appetite
Pyrexia (fever)
Febrile neutropenia (fever with reduced white blood cells)
Aphthous stomatitis (mouth ulcer)
Difficulty in walking
Dysstasia (difficulty in standing)
Pain in extremity
Rhabdomyolysis (a condition in which damaged skeletal muscle tissue breaks down)

10-19:

n/a

20-29:

n/a

30-39:

Cellulitis (infection under the skin)
Cervical dysplasia (abnormal changes in the cells on the surface of the cervix)
Convulsion (muscles contract and relax rapidly and repeatedly, resulting in an uncontrolled shaking of the body)
Cough
Crying
Cyst (a closed sac)
Dehydration (dryness resulting from the removal of water)
Drug abuse
Drug abuser
Drug screen positive

40-49:

Anxiety
Chronic kidney disease
Depression
Renal failure (kidney dysfunction)
Suicidal ideation
Nephrogenic anaemia (anaemia due to kidney disease)
Renal injury (kidney injury)
Suicide attempt

50-59:

Acute respiratory failure
Anaemia (lack of blood)
Anaemia of chronic disease
Asthma
Atrioventricular block first degree (heart block first degree)
Benign bone neoplasm (benign (non-cancerous) tumours of the bone)
Blister (small pocket of fluid within the upper layers of the skin caused by forceful rubbing (friction), burning, freezing, chemical exposure)
Bronchopneumonia (inflammation of the lungs, arising in the bronchi or bronchioles)
Cardiac failure congestive
Cellulitis (infection under the skin)

60+:

Fatigue (feeling of tiredness)
Headache (pain in head)
Chest pain
Death
Diarrhoea
Dyspnoea (difficult or laboured respiration)
Epistaxis (bleed from the nose)
Hypersomnia (excessive daytime sleepiness (eds))
Hypoaesthesia (reduced sense of touch or sensation)
Nausea (feeling of having an urge to vomit)

What are the existing conditions these people have? *

Hypothyroidism (abnormally low activity of the thyroid gland, resulting in retardation of growth and mental development): 5 people, 33.33%
Neuralgia (pain in one or more nerves): 5 people, 33.33%
Fibromyalgia (a long-term condition which causes pain all over the body): 4 people, 26.67%
Wheezing (a high-pitched whistling sound made while you breath): 4 people, 26.67%
Dizziness: 3 people, 20.00%
Rheumatoid Arthritis (a chronic progressive disease causing inflammation in the joints): 3 people, 20.00%
Infection: 3 people, 20.00%
Pain: 3 people, 20.00%
Neck Pain: 3 people, 20.00%
High Blood Cholesterol: 3 people, 20.00%

* Approximation only. Some reports may have incomplete information.

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