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

Summary:

Drug interactions are reported among people who take Synthroid (levothyroxine sodium) and Mephyton (phytonadione). Common drug interactions include nephrogenic anaemia among females and pneumonia among males.

The phase IV clinical study analyzes what interactions people have when they take Synthroid and Mephyton. It is created by eHealthMe based on reports of 38 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 Mephyton?

Mephyton has active ingredients of phytonadione. eHealthMe is studying from 1,006 Mephyton users. Check the latest studies of Mephyton.

On Jul, 20, 2026

38 people who take Synthroid and Mephyton together, and have interactions are studied.

Synthroid and Mephyton drug interactions.

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

female:

Nephrogenic anaemia (anaemia due to kidney disease)
Nervousness
Neutropenia (an abnormally low number of neutrophils)
Oedema peripheral (superficial swelling)
Oesophageal varices haemorrhage (bleeding from extremely dilated sub-mucosal veins in the lower third of the oesophagus)
Overdose
Oxygen saturation decreased
Pain in extremity
Pancarditis (inflammation of the entire heart)
Pancreatitis (inflammation of pancreas)

male:

Pneumonia
Chronic sinusitis (long lasting inflammation of the paranasal sinuses)
Leukaemia recurrent (repeat cancer of bone marrow or blood cells)
Pleural effusion (water on the lungs)
Pyrexia (fever)
Tachycardia (a heart rate that exceeds the range of 100 beats/min)
Anaemia (lack of blood)
Cardiac failure congestive
Herpes zoster
International normalised ratio increased

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

0-1:

n/a

2-9:

n/a

10-19:

Pancarditis (inflammation of the entire heart)
Pancreatitis (inflammation of pancreas)

20-29:

n/a

30-39:

n/a

40-49:

Dyspnoea (difficult or laboured respiration)
Heart rate increased
Infective pulmonary exacerbation of cystic fibrosis (severe infective lung disease with production of abnormally thick mucus)
Thyroid cancer

50-59:

Arthritis (form of joint disorder that involves inflammation of one or more joints)
Back pain
Bronchitis (inflammation of the mucous membrane in the bronchial tubes)
Cardiac disorder
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)
Chronic obstructive pulmonary disease (a progressive disease that makes it hard to breathe)
Death
Insomnia (sleeplessness)
International normalised ratio increased
Jugular vein thrombosis (clot in jugular vein)

60+:

Acute respiratory failure
Hypotension (abnormally low blood pressure)
Adverse drug reaction
Ankle fracture
Ascites (accumulation of fluid in the abdominal cavity)
Drug ineffective
Hepatic neoplasm malignant (liver cancer)
Herpes zoster
Limb injury
Weakness

What are the existing conditions these people have? *

Gastroesophageal Reflux Disease (a condition in which stomach contents leak backward from the stomach into the oesophagus): 9 people, 23.68%
High Blood Pressure: 8 people, 21.05%
Arthritis (form of joint disorder that involves inflammation of one or more joints): 6 people, 15.79%
Diabetes: 6 people, 15.79%
High Blood Cholesterol: 6 people, 15.79%
Blister (small pocket of fluid within the upper layers of the skin caused by forceful rubbing (friction), burning, freezing, chemical exposure): 5 people, 13.16%
Fungal Infection: 5 people, 13.16%
Psoriasis (immune-mediated disease that affects the skin): 5 people, 13.16%
Acute Myeloid Leukaemia (acute cancer in which the bone marrow makes abnormal myeloblasts): 5 people, 13.16%
Cystic Fibrosis (disease of the secretary glands): 4 people, 10.53%

* Approximation only. Some reports may have incomplete information.

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