no thyroid, weight loss

I have a client who lost about 25 pounds with Take Shape For Life using Medifast foods. She does not have a thyroid and take medications for hypothyroidism. She hit a plateau recently, has added some exercise, and is losing again, but very slowly. She does not use a soy product close to the time she takes her medication. Is there anything that can help her with her weight loss?
I have other clients who are hypothyroid and are not having the same issues.
I appreciate any advice you can give me for her.

[gimel]

What hypothyroid symptoms does she have?   It would help members make an assessment and respond if thyroid lab results and their reference ranges were posted.

[redheadaussie]

Depending on her age, her dosage of thyroid replacement medication, lifestyle, stress,  weight she already is, time of year...there are many factors in the hypothyroid disease of losing weight.
I for one, weighed over 220 lbs and lost around 80 or so being hypo and undiagnosed. The body will naturally get to a plateau, then it is time to up the physical work, make it harder, and the weight should move again.
You say she is losing slowly. That is how it should be. The body does not like rapid weight loss and will act accordingly! If she has stopped using the Medifast diet her weight may increase.
It is vital she has her blood tests done and to see if she is truly hypothyroid. If so her medication will need adjusting and she should keep the weight down, provided she eats healthily and continues to do physical excersise.