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

Summary:

Drug interactions are reported among people who take Keflex (cephalexin) and Levothroid (levothyroxine sodium). Common drug interactions include abdominal pain upper among females and asthenia among males.

The phase IV clinical study analyzes what interactions people have when they take Keflex and Levothroid. It is created by eHealthMe based on reports of 36 people who take the same drugs from the FDA, and is updated regularly.

What is Keflex?

Keflex has active ingredients of cephalexin. It is often used in infection. eHealthMe is studying from 15,844 Keflex users. Check the latest studies of Keflex.

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.

eHealthMe: drug outcomes in the real world

eHealthMe runs one of the largest post-marketing drug safety studies in the world. We study millions of patients and 5,000 more each day. Our data-driven phase IV clinical trials have been referenced on 800+ peer-reviewed medical publications including The Lancet, Mayo Clinic Proceedings, and Nature. Tools to study our phase IV findings are available to the public, anonymous and free >>>.

On Sep, 02, 2026

36 people who take Keflex and Levothroid together, and have interactions are studied.

Keflex and Levothroid drug interactions.

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

female:

Abdominal pain upper
Ankle fracture
Arthropathy
Blood magnesium decreased
Blood osmolarity decreased
Blood pressure systolic increased
Bone pain
Change of bowel habit
Chest pain
Constipation

male:

Asthenia (weakness)
Decreased appetite
Anaemia (lack of blood)
Gastrointestinal haemorrhage (bleeding gastrointestinal tract)
Alopecia (absence of hair from areas of the body)
Back pain
Cerebellar ataxia (loss of coordination)
Cerebellar atrophy (degeneration of the section of the brain responsible for balance, voluntary muscle movements)
Cerebral ischaemia (insufficient blood flow to the brain to meet metabolic demand)
Cognitive disorder (mental health disorders affects learning, memory, perception, and problem solving)

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

0-1:

n/a

2-9:

n/a

10-19:

n/a

20-29:

n/a

30-39:

n/a

40-49:

Back pain
Cerebellar ataxia (loss of coordination)
Cerebellar atrophy (degeneration of the section of the brain responsible for balance, voluntary muscle movements)
Cerebral ischaemia (insufficient blood flow to the brain to meet metabolic demand)
Cognitive disorder (mental health disorders affects learning, memory, perception, and problem solving)
Diplopia (double vision)
Dizziness
Dysarthria (speech disorder)
Encephalitis (inflammation of the brain)
Erection increased

50-59:

Abdominal pain
Ankle fracture
Arthropathy
Bone pain
Chest pain
Drug ineffective
Excoriation (to tear or wear off the skin of)
Gastrointestinal obstruction
Gastrointestinal ulcer
Headache (pain in head)

60+:

Adverse event
Blood glucose increased
Asthenia (weakness)
Decreased appetite
Dehydration (dryness resulting from the removal of water)
Diverticulitis (digestive disease which involves the formation of pouches (diverticula) within the bowel wall)
Drug ineffective
Drug intolerance (drug sensitivity)
Fatigue (feeling of tiredness)
Feeding disorder (when children refuse to eat certain food groups)

What are the existing conditions these people have? *

Neuropathy Peripheral (surface nerve damage): 6 people, 16.67%
Pain: 6 people, 16.67%
Atrial Fibrillation/flutter (atrial fibrillation and flutter are abnormal heart rhythms in which the atria, or upper chambers of the heart, are out of sync with the ventricles): 5 people, 13.89%
High Blood Cholesterol: 4 people, 11.11%
High Blood Pressure: 4 people, 11.11%
Diabetic Neuropathy (neuropathic disorders that are associated with diabetes mellitus): 4 people, 11.11%
Prostate Cancer: 3 people, 8.33%
Restless Leg Syndrome (a powerful urge to move your legs): 3 people, 8.33%
Depression: 3 people, 8.33%
Rheumatoid Arthritis (a chronic progressive disease causing inflammation in the joints): 3 people, 8.33%

* Approximation only. Some reports may have incomplete information.

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