Fiorinal and Skelaxin drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Fiorinal (aspirin; butalbital; caffeine) and Skelaxin (metaxalone). Common drug interactions include diarrhoea among females and aggression among males.

The phase IV clinical study analyzes what interactions people have when they take Fiorinal and Skelaxin. It is created by eHealthMe based on reports of 41 people who take the same drugs from the FDA, and is updated regularly.

What is Fiorinal?

Fiorinal has active ingredients of aspirin; butalbital; caffeine. It is often used in migraine. eHealthMe is studying from 2,714 Fiorinal users. Check the latest studies of Fiorinal.

What is Skelaxin?

Skelaxin has active ingredients of metaxalone. It is often used in back pain. eHealthMe is studying from 9,706 Skelaxin users. Check the latest studies of Skelaxin.

On Jul, 14, 2026

41 people who take Fiorinal and Skelaxin together, and have interactions are studied.

Fiorinal and Skelaxin drug interactions.

What are the common drug interactions of Fiorinal and Skelaxin, by gender? *:

female:

Diarrhoea
Drug dependence
Dysphagia (a condition in which swallowing is difficult or painful)
Impaired work ability
Malaise (a feeling of general discomfort or uneasiness)
Neck pain
Oedema peripheral (superficial swelling)
Pulmonary embolism (blockage of the main artery of the lung)
Sleep apnoea syndrome (a sleep-related disorder in which the effort to breathe is diminished or absent)
Arrhythmia (irregular heartbeat)

male:

Aggression
Anxiety
Balanitis candida (inflammation of the glands penis by infection with candida albicans)
Bronchitis (inflammation of the mucous membrane in the bronchial tubes)
Bursitis (inflammation of a bursa, typically one in the knee, elbow, or shoulder)
Cardiac failure congestive
Cardiomegaly (increased size of heart than normal)
Carotid artery disease
Cellulitis of male external genital organ (infection of male genitals soft tissue)
Chest discomfort

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

0-1:

n/a

2-9:

n/a

10-19:

n/a

20-29:

Accident
Drug dependence
Injury

30-39:

Abdominal pain
Alopecia (absence of hair from areas of the body)
Anxiety
Cholelithiasis (the presence or formation of gallstones in the gallbladder or bile ducts)
Deafness unilateral
Deep vein thrombosis (blood clot in a major vein that usually develops in the legs and/or pelvis)
Drug dependence
Emotional distress
Hepatitis b
Malaise (a feeling of general discomfort or uneasiness)

40-49:

Abdominal pain upper
Anxiety
Arrhythmia (irregular heartbeat)
Asthenia (weakness)
Balance disorder
Balanitis candida (inflammation of the glands penis by infection with candida albicans)
Bronchitis (inflammation of the mucous membrane in the bronchial tubes)
Bursitis (inflammation of a bursa, typically one in the knee, elbow, or shoulder)
Cardiac failure congestive
Cardiomegaly (increased size of heart than normal)

50-59:

Chronic kidney disease
Completed suicide (act of taking one's own life)
Dehydration (dryness resulting from the removal of water)
Drug intolerance (drug sensitivity)
Dysphagia (a condition in which swallowing is difficult or painful)
Fatigue (feeling of tiredness)
Hangover
Impaired work ability
Increased appetite
Malaise (a feeling of general discomfort or uneasiness)

60+:

Anxiety
Intervertebral disc protrusion (spinal disc protrusion)
Affect lability (emotional incontinence)
Anaemia (lack of blood)
Ankle fracture
Anosognosia (ignorance of the presence of disease)
Aortic arteriosclerosis (hardening of the aortic arteries)
Apathy
Bronchitis (inflammation of the mucous membrane in the bronchial tubes)
Bruxism (habitual grinding of the teeth, typically during sleep)

What are the existing conditions these people have? *

Narcolepsy (brain's inability to regulate sleep-wake cycles normally): 18 people, 43.90%
Pain: 5 people, 12.20%
Stress And Anxiety: 4 people, 9.76%
Sleep Disorder: 4 people, 9.76%
Gastroesophageal Reflux Disease (a condition in which stomach contents leak backward from the stomach into the oesophagus): 3 people, 7.32%

* Approximation only. Some reports may have incomplete information.

Do you take Fiorinal and Skelaxin?

- 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