The best person to ask about drug interactions is your doctor or pharmacist. If there are interactions it may just be a matter of timing your meds so that they don't interfere with one another..
What's your thyroid related question?
Excerpt from Gallbladder Attack - Stomach Acid...
"Too much stomach acid? Really? I mean, how is it that millions of people on PPIs are making too much HCl? Hyperchlorhydria or too much stomach acid is rather rare. If you're overeating, eating junk food or other food that is hard to digest, eating when stressed, living under stress, chances are much greater that you don't make enough hydrochloric acid or digestive enzymes and your symptoms stem from that. Take a look at some of the symptoms caused by low stomach acid.
Signs of Deficient Stomach Acid
Gas, bloating and burping shortly after a meal could be lack of HCl
Constipation
Diarrhea
Feeling of fullness or food not digesting
Heartburn and/or gastric reflux (sometimes too much HCl but most often not enough)
Bad breath
Foul smelling stools
Loose stools in the early morning
Food allergies
Dialated blood vessels on the cheeks and nose - Rosacea
Pernicious anemia or iron deficiency
Anal Itching
Nausea especially after taking vitamins and minerals
Weak or cracked nails
Parasites - or at least increased susceptibility to parasitic infections
Chronic yeast infections
Acne in adults - especially if you have other symptoms from the list
Asthma
Since low levels of stomach acid results in poor absorption of nutrients, many symptoms that accompany a deficiency of that vitamin or mineral makes this list much longer. The nutrients most affected are calcium, iron, folic acid, vitamin K and many B vitamins. See pernicious anemia.
If you're nervous about trying supplemental hydrochloric acid, you can do a trial with 1-2 TBSP of organic apple cider vinegar mixed with 1/8 to 1/4 cup of water after a meal. If it makes you feel better and does not hurt, you most likely would benefit from taking 500 - 1000 mg. of Betaine HCl with your meals."