Cytomel speeds up your metabolism, but it can also make you hungrier because you process your food so much quicker. Cytomel also chews the shit outta lean body mass.
Lean body mass is the only place that fat burns, so in the end, she may end up fatter, but smaller overall, with less future ability to burn fat in the muscle if she ever starts exercising right.
Cytomel can also kill natural production of thyroid, leaving her on the drug forever.
Drug has some other nasty side effects too:
High blood pressure
A rapid heart rate (tachycardia)
An irregular heart rhythm (arrhythmia)
Heart failure, chest pain, or a heart attack
Heart palpitations
An increased appetite, along with weight loss
Feeling hot all the time and increased sweating
Fever
Hyperactivity, nervousness, anxiety, or irritability
Insomnia
Emotional changes
Shakiness or muscle weakness
Difficult or painful breathing
Diarrhea, vomiting, or abdominal cramps (stomach cramps)
Hair loss
Flushing
Broken bones or other signs of weakened bones
Difficulty breathing, especially if accompanied by fluid retention in the legs or feet (signs of congestive heart failure or CHF)
Menstrual problems or fertility problems