Hypersensitivity reactions to Synthroid are more common among those who have allergies, hay fever, or asthma.
People who have asthma are also more likely to be allergic.
For some people with hypothyroidism who have these allergies, taking Synthroid can cause allergic symptoms.
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Lactose
Another ingredient in Synthroid is lactose, which can trigger symptoms in people with lactose intolerance.
Lactose intolerance is an inability to digest lactose, the major sugar found in milk.
Lactose is also an ingredient in some foods and medications.
Get our printable guide for your next doctor’s appointment to help you ask the right questions.
Signs of lactose intolerance may include abdominal pain, cramps, bloating, gas, nausea, and diarrhea.
With lactose intolerance, these symptoms often begin 30 minutes to two hours after taking Synthroid.
A 2017 study looked specifically at the gluten content of Synthroid tablets.
Some people develop an eczematous-throw in rash, hives, or widespread itching.
Signs of a cornstarch allergy can depend on the underlying sensitivity.
With a corn allergy, symptoms may range from hives to hay fever, to anaphylaxis.
While allergic reactions to Synthroid are uncommon, any allergic reaction has the potential to be life-threatening.
If you are concerned, keeping a daily diary of symptoms may be helpful.
What she will recommend depends, in large part, on the severity of the reaction you are having.
Lactase supplements themselves, however, may trigger allergic reactions in some people.
Levoxyl and Tirosint are brands of levothyroxine that are free of both acacia and lactose.
There are also other brands of levothyroxine such as Levothroid and Unithroid.
Fortunately, there are other brands of levothyroxine available if switching your medication is considered.
Get our printable guide for your next doctor’s appointment to help you ask the right questions.
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