Oyster shell and Allopurinol drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Oyster shell (calcium) and Allopurinol (allopurinol). Common drug interactions include dysphonia among females and asthenia among males.

The phase IV clinical study analyzes what interactions people have when they take Oyster shell and Allopurinol. It is created by eHealthMe based on reports of 54 people who take the same drugs from the FDA, and is updated regularly.

What is Oyster shell?

Oyster shell has active ingredients of calcium. eHealthMe is studying from 731 Oyster shell users. Check the latest studies of Oyster shell.

What is Allopurinol?

Allopurinol has active ingredients of allopurinol. It is often used in gout. eHealthMe is studying from 190,868 Allopurinol users. Check the latest studies of Allopurinol.

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 Aug, 24, 2026

54 people who take Oyster shell and Allopurinol together, and have interactions are studied.

Oyster shell and Allopurinol drug interactions.

What are the common drug interactions of Oyster Shell and Allopurinol, by gender? *:

female:

Dysphonia (speech disorder attributable to a disorder of phonation)
Eating disorder
Electrolyte imbalance
Escherichia sepsis (bacterial infection by escherichia coli)
Escherichia urinary tract infection (urinary tract infection by escherichia coli)
Eye pain
Fatigue (feeling of tiredness)
Febrile neutropenia (fever with reduced white blood cells)
Febrile nonhaemolytic transfusion reaction (reaction with fever)
Gait disturbance

male:

Asthenia (weakness)
Renal failure (kidney dysfunction)
Bronchitis (inflammation of the mucous membrane in the bronchial tubes)
Fluid intake reduced
Right ventricular failure (right half of the heart fails to work)
Cardiac arrest
Herpes zoster
Atrial fibrillation (fibrillation of the muscles of the atria of the heart)
Blood osmolarity decreased
Cardiovascular insufficiency (inadequate functioning of heart)

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

0-1:

n/a

2-9:

n/a

10-19:

n/a

20-29:

Acute lymphocytic leukaemia recurrent (cancer in which the bone marrow makes too many lymphocytes-recurrent)
Blood creatinine increased
Clostridium difficile colitis (inflammation of colon by clostridium difficile bacteria infection)
Depression
Disease progression
Eating disorder
Electrolyte imbalance
Escherichia sepsis (bacterial infection by escherichia coli)
Febrile neutropenia (fever with reduced white blood cells)
Febrile nonhaemolytic transfusion reaction (reaction with fever)

30-39:

n/a

40-49:

Dyspnoea (difficult or laboured respiration)
Pneumonia
Red blood cell abnormality (abnormal red blood cells)

50-59:

Asthenia (weakness)
Drug level decreased
Loss of consciousness
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)
Myocardial infarction (destruction of heart tissue resulting from obstruction of the blood supply to the heart muscle)
Back injury
Loss of libido (loss of sexual urge)
Pulmonary mass
Pulmonary oedema (fluid accumulation in the lungs)

60+:

Decreased appetite
Fatigue (feeling of tiredness)
Bone pain
Dyspnoea (difficult or laboured respiration)
Gait disturbance
Headache (pain in head)
Intervertebral disc protrusion (spinal disc protrusion)
Irritability
Neck pain
Pain

What are the existing conditions these people have? *

Multiple Myeloma (cancer of the plasma cells): 10 people, 18.52%
High Blood Pressure: 7 people, 12.96%
Rheumatoid Arthritis (a chronic progressive disease causing inflammation in the joints): 6 people, 11.11%
Blood Pressure Abnormal: 5 people, 9.26%
Combined Immunodeficiency: 5 people, 9.26%
Gouty Arthritis (joint inflammation with crystal formation): 5 people, 9.26%
High Blood Cholesterol: 5 people, 9.26%
Urination - Excessive Volume: 4 people, 7.41%
Blood Uric Acid Abnormal: 4 people, 7.41%
Cardiac Discomfort: 4 people, 7.41%

* Approximation only. Some reports may have incomplete information.

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