Tecfidera and Levothroid drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Tecfidera (dimethyl fumarate) and Levothroid (levothyroxine sodium). Common drug interactions include dyspnoea among females and flushing among males.

The phase IV clinical study analyzes what interactions people have when they take Tecfidera and Levothroid. It is created by eHealthMe based on reports of 73 people who take the same drugs from the FDA, and is updated regularly.

What is Tecfidera?

Tecfidera has active ingredients of dimethyl fumarate. It is often used in multiple sclerosis. eHealthMe is studying from 129,627 Tecfidera users. Check the latest studies of Tecfidera.

What is Levothroid?

Levothroid has active ingredients of levothyroxine sodium. It is often used in hypothyroidism. eHealthMe is studying from 8,974 Levothroid users. Check the latest studies of Levothroid.

On Jul, 12, 2026

73 people who take Tecfidera and Levothroid together, and have interactions are studied.

Tecfidera and Levothroid drug interactions.

What are the common drug interactions of Tecfidera and Levothroid, by gender? *:

female:

Dyspnoea (difficult or laboured respiration)
Dysstasia (difficulty in standing)
Dysuria (painful or difficult urination)
Eye swelling
Febrile infection (infection with temperature rise)
Gait disturbance
Hip arthroplasty
Influenza like illness
Intracranial aneurysm (bulging, weak area in the wall of a cranial artery)
Limb discomfort (discomfort in leg)

male:

Flushing (the warm, red condition of human skin)
Paraesthesia (sensation of tingling, tickling, prickling, pricking, or burning of a person's skin with no apparent long-term physical effect)
Diabetes mellitus (diabetes, caused by a deficiency of the pancreatic hormone insulin)
General physical health deterioration (weak health status)
Lymphocyte count decreased
Shoulder operation
Anger
Asthenia (weakness)
Bladder disorder
Decreased appetite

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

0-1:

n/a

2-9:

n/a

10-19:

n/a

20-29:

Balance disorder
Hypoaesthesia (reduced sense of touch or sensation)
Muscle spasms (muscle contraction)
Optic neuritis (optic nerve inflammation)

30-39:

n/a

40-49:

Restless legs syndrome (a powerful urge to move your legs)
Vertigo
Abdominal pain upper
Ankle fracture
Diarrhoea
Fall
Fungal infection
Gastrooesophageal reflux disease (stomach contents (food or liquid) leak backwards from the stomach into the oesophagus)
Impaired healing
Localised infection (infection at the single location)

50-59:

Ankle fracture
Fall
Femur fracture
Hip fracture
Lower limb fracture
Memory impairment
Schizoaffective disorder (a mental disorder characterized by disordered thought)
Speech disorder
Alanine aminotransferase increased
Alopecia (absence of hair from areas of the body)

60+:

Flushing (the warm, red condition of human skin)
Rash
Appendicitis perforated (perforated appendicitis is a condition in which an inflamed appendix bursts)
Musculoskeletal disorder (disease of the body's muscles, joints, tendons, ligaments and nerves)
Postoperative ileus
Squamous cell carcinoma (a cancer of a kind of epithelial cell)
Death
Feeling hot
Headache (pain in head)
Muscular weakness (muscle weakness)

* Approximation only. Some reports may have incomplete information.

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