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Levothyroxine side effects

Aggregated from 4 medical sources. Not medical advice. Always consult a healthcare professional.

47 side effects

Side effectFrequencyMedlinePlusPubMed CentralWebMDBuzzrx.com
Anxietycommonanxietynervousness
Arrhythmiascommonrapid or irregular heartbeat or pulseArrhythmiasirregular heartbeat (arrhythmias or heart rhythm abnormalities)
Black tongue
Bloody stools
Breathing problemsrareshortness of breathBreathing problems or wheezing
Cancercancer
Chest painrarechest painChest pain or pressureChest pain (angina)
Confusionconfusion
Crampscommonleg crampsMuscle spasms or weaknessLeg cramps
DizzinessrareDizziness, feeling lightheaded, or fainting
DiarrheacommondiarrheaDiarrheaDiarrhea
Difficulty sleepingcommondifficulty falling asleepTrouble sleepingProblems sleeping
Excessive sweatingcommonexcessive sweatingSweating
FevercommonfeverFever or general ill feelingFever
Flushingflushing
Fracturesfractures
Hair lossrarehair losshair loss
HeadachecommonheadacheHeadache
Heart attackcommonHeart attack
Heart diseaseheart disease
HivesrarehivesItching, skin rash, or pale red bumps on the skin called hives
Increased appetitecommonchanges in appetiteIncreased appetiteIncrease in appetite
Irregular heartbeatrarerapid or irregular heartbeat or pulseRacing heartIncrease in heart rate
ItchingrareitchingItching, skin rash, or pale red bumps on the skin called hives
Joint paincommonjoint painJoint painJoint pain
Leg crampscommonleg crampsLeg cramps
Loss of consciousnessrareloss of consciousnessDizziness, feeling lightheaded, or fainting
Menstrual changescommonchanges in menstrual cycleMenstrual changesChanges in menstrual cycle
Muscle spasmscommonMuscle spasms or weaknessMuscle cramps
Nauseavery commonnauseaNausea or vomitingNausea
NervousnesscommonnervousnessNervousness
OsteopeniauncommonOsteopenia
OsteoporosisuncommonosteoporosisOsteoporosisIncreased bone resorption and decreased bone mineral density
RashcommonrashSkin rash
Racing heartrareRacing heart
Seizureseizure
Sensitivity to heatcommonsensitivity to heatTrouble tolerating heatSensitivity to heat
Shortness of breathcommonshortness of breathShortness of breath
Skin rashcommonSkin rash
Stomach crampsrareStomach cramps
Stomach painstomach pain
Swellingrareswelling of hands, feet, ankles, or lower legsSwelling of the face, lips, mouth, tongue, or throat
Tremorscommonuncontrollable shakingTremorsShakiness, especially in the hands
Trouble swallowingrareTrouble swallowing or throat tightness
VomitingcommonvomitingNausea or vomitingVomiting
Weight changescommonweight gain or lossWeight changes
WheezingrarewheezingBreathing problems or wheezing

2 additional sourcesdidn't return structured side-effect data: Mayo Clinic, GoodRx.

Demographic risk groups

GroupRiskSources
infantdifficulty swallowingMedlinePlus
childdifficulty swallowingMedlinePlus
adultdifficulty swallowingMedlinePlus
pregnantunknownMedlinePlus
breastfeedingunknownMedlinePlus
renal impairmentunknownMedlinePlus
liver diseaseunknownMedlinePlus
childrenmedication accessMedlinePlus, PubMed Central
femalesmore inclined towards femalesPubMed Central
adultsprevalence of SCHPubMed Central
menopausehigher risk of osteoporosisWebMD
elderlygreater risk of some side effectsWebMD
Elderly patientsHigher risk of cardiovascular problemsBuzzrx.com
Post-menopausal womenHigher risk of osteoporosisBuzzrx.com
Older adults and people with pre-existing heart conditionsIncreased risk of heart diseaseBuzzrx.com
Post-menopausal women and elderly patients above 70 years of ageIncreased risk of osteoporosis and bone fracturesBuzzrx.com
People with adrenal insufficiencyAcute adrenal crisisBuzzrx.com
Diabetics being treated with certain medicationsWorsening glycemic controlBuzzrx.com

Medside aggregates publicly available side-effect information for reference only. It is not medical advice. Always consult a healthcare professional before making decisions about medication.

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