Flexeril and Kefzol drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Flexeril (cyclobenzaprine hydrochloride) and Kefzol (cefazolin sodium). Common drug interactions include cor pulmonale chronic among females and cardio-respiratory arrest among males.

The phase IV clinical study analyzes what interactions people have when they take Flexeril and Kefzol. It is created by eHealthMe based on reports of 37 people who take the same drugs from the FDA, and is updated regularly.

What is Flexeril?

Flexeril has active ingredients of cyclobenzaprine hydrochloride. It is often used in muscle spasms. eHealthMe is studying from 38,308 Flexeril users. Check the latest studies of Flexeril.

What is Kefzol?

Kefzol has active ingredients of cefazolin sodium. eHealthMe is studying from 628 Kefzol users. Check the latest studies of Kefzol.

On Jul, 04, 2026

37 people who take Flexeril and Kefzol together, and have interactions are studied.

What are the common drug interactions of Flexeril and Kefzol, by gender? *:

female:

Cor pulmonale chronic (long lasting enlargement of the right ventricle of the heart)
Gastroduodenitis (an inflammation of the mucous membrane of the stomach and duodenum)
Nausea (feeling of having an urge to vomit)
Uterine enlargement
Weight decreased
Cardiac failure congestive
Pain
Appendicitis (inflammation of the appendix)
Aptyalism (deficiency or absence of saliva)
Asthma

male:

Cardio-respiratory arrest (sudden dysfunction of heart and lungs)
Diabetes mellitus (diabetes, caused by a deficiency of the pancreatic hormone insulin)
Osteoarthritis (a joint disease caused by cartilage loss in a joint)
Peritonitis (inflammation of the peritoneum, the thin tissue that lines the inner wall of the abdomen and covers most of the abdominal organs)
Renal impairment (severely reduced kidney function)
Diabetic retinopathy (damage to the retina caused by complications of diabetes)
Hepatic cirrhosis (chronic liver disease characterized by replacement of liver tissue by fibrosis, scar tissue)
Hepatic encephalopathy (spectrum of neuropsychiatric abnormalities in patients with liver failure)
Hepatic failure (liver failure)
Hepatic neoplasm malignant (liver cancer)

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

0-1:

n/a

2-9:

n/a

10-19:

n/a

20-29:

Cholecystitis chronic (long lasting infection of gallbladder)
Cholelithiasis (the presence or formation of gallstones in the gallbladder or bile ducts)
Gallbladder disorder
Gallbladder non-functioning
Injury
Pain

30-39:

Diabetes mellitus (diabetes, caused by a deficiency of the pancreatic hormone insulin)
Diabetic retinopathy (damage to the retina caused by complications of diabetes)

40-49:

Nephrogenic systemic fibrosis (involves fibrosis of skin, joints, eyes due to kidney disease)

50-59:

Appendicitis (inflammation of the appendix)
Weight decreased
Nausea (feeling of having an urge to vomit)
Cardiac failure congestive
Aptyalism (deficiency or absence of saliva)
Asthma
Bone disorder
Bone erosion
Bone fragmentation
Bone pain

60+:

Anxiety
Cardiac arrest
Drug hypersensitivity
Emotional distress
Fear
Injury
Osteoarthritis (a joint disease caused by cartilage loss in a joint)
Pain
Stress
Ventricular fibrillation (abnormally irregular heart rhythm)

What are the existing conditions these people have? *

Systemic Lupus Erythematosus (an autoimmune disease, which means the body's immune system mistakenly, attacks healthy tissue): 27 people, 72.97%
Osteoporosis (bones weak and more likely to break): 27 people, 72.97%
Thrombocytopenia (decrease of platelets in blood): 11 people, 29.73%
Menstruation Irregular: 3 people, 8.11%

* Approximation only. Some reports may have incomplete information.

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