Hi Nikki,
Congratulations, you ave done a wonderful job! You have taken control of your weight and eating and understand what you put into your bodys does count, plus you have lost 55 pounds i 5 months!
Now for your question.
1) Alli is most effective for about 6 months, then the weight loss will slow down. Our bodies like to hold on to the calories we eat and adapt quite easily to a change in diet, caloric intake and an exercise routine. If you still need to reach your target weight, alli will continue working but it will take longer, possibly 1/2-1 pound per week rather than 1-2 pounds.
2)Your Gi tract adjust to the effects of alli, so that you can become more tolerant of higher fat. It is not that alli is not blocking the same amount of fat, but your GI tract can handle the extra. But do note that a treatment effect can occur upto 72 hours after a high fat meal.
Continued success. Hope this helps.
Sophia De Monte RPh