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[Date of letter-month, day, and year]

[Recipient's first and last names]
[Company name]
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Dear [recipient's name]:

I recently received a diagnosis from Dr. Smith at Lakes Endocrinology, which indicated that I have hypothyroidism, according to tests Dr. Smith ordered. However, I am unsure of whether this diagnosis is accurate and would like to verify the prognosis. Therefore, I am requesting an appointment with one of the doctors in your office so that I can receive a second opinion and further guidance.

Please contact me at 954-9235 so that I can obtain more information and schedule an appointment. I look forward to hearing from you soon.

Sincerely,

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[Sender's first and last names]