Synthroid and Rivasa drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Synthroid (levothyroxine sodium) and Rivasa (acetylsalicylic acid). Common drug interactions include arthralgia among females and cataract among males.

The phase IV clinical study analyzes what interactions people have when they take Synthroid and Rivasa. It is created by eHealthMe based on reports of 16 people who take the same drugs from the FDA, and is updated regularly.

What is Synthroid?

Synthroid has active ingredients of levothyroxine sodium. It is often used in hypothyroidism. eHealthMe is studying from 249,198 Synthroid users. Check the latest studies of Synthroid.

What is Rivasa?

Rivasa has active ingredients of acetylsalicylic acid. eHealthMe is studying from 107 Rivasa users. Check the latest studies of Rivasa.

On Jul, 12, 2026

16 people who take Synthroid and Rivasa together, and have interactions are studied.

What are the common drug interactions of Synthroid and Rivasa, by gender? *:

female:

Arthralgia (joint pain)
Asthma
Blister (small pocket of fluid within the upper layers of the skin caused by forceful rubbing (friction), burning, freezing, chemical exposure)
Chills (felling of cold)
Dizziness
Dyspnoea (difficult or laboured respiration)
Fatigue (feeling of tiredness)
Headache (pain in head)
Lymphoedema (localized fluid retention and tissue swelling)
Oropharyngeal pain

male:

Cataract (clouding of the lens inside the eye)
Colitis ulcerative (inflammation of colon with ulcer)
Asthenia (weakness)
Dizziness
Dyspnoea (difficult or laboured respiration)
Erythema (redness of the skin)
Faeces discoloured
Fatigue (feeling of tiredness)
Haematochezia (passage of stools containing blood)
Hypertension (high blood pressure)

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

0-1:

n/a

2-9:

n/a

10-19:

n/a

20-29:

n/a

30-39:

Arthralgia (joint pain)
Dysuria (painful or difficult urination)
Muscle spasms (muscle contraction)
Nausea (feeling of having an urge to vomit)

40-49:

n/a

50-59:

n/a

60+:

Cataract (clouding of the lens inside the eye)
Colitis ulcerative (inflammation of colon with ulcer)
Chills (felling of cold)
Headache (pain in head)
Lymphoedema (localized fluid retention and tissue swelling)
Oropharyngeal pain
Pulmonary fibrosis (formation or development of excess fibrous connective tissue (fibrosis) in the lungs)
Pyrexia (fever)
Rash
Wound

What are the existing conditions these people have? *

Rheumatoid Arthritis (a chronic progressive disease causing inflammation in the joints): 5 people, 31.25%
Ulcerative Colitis (inflammatory bowel disease (ibd). it causes swelling, ulcerations, and loss of function of the large intestine): 4 people, 25.00%
Joint Pain: 3 people, 18.75%
Prostate Cancer: 2 people, 12.50%
High Blood Cholesterol: 2 people, 12.50%
Deep Venous Thrombosis (blood clot in a major vein that usually develops in the legs and/or pelvis): 2 people, 12.50%
Musculoskeletal Pain (pain affects the bones, muscles, ligaments, tendons, and nerves): 1 person, 6.25%
Crohn's Disease (a condition that causes inflammation of the gastrointestinal tract): 1 person, 6.25%
Behcet's Syndrome (involves inflammation of the blood vessels): 1 person, 6.25%

* Approximation only. Some reports may have incomplete information.

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