How to gain weight?

[autumxx]

I am a 16 year old female. I take adhd medication which causes loss of appetite. My doctor said I'm not skinny and I'm not fat. I am 4'11 and weigh 89 lbs. I feel like I'm skinny even though my doctor said I'm not. I have been trying to gain muscle weight but it's hard with a small appetite. Does anybody have any suggestions on how I can gain weight and increase my appetite?

[boron]

Obviously you are finding the loss of appetite due to ADHD drugs as a problem, so you can ask your current or another doctor should you continue with the drugs or not. It is not only your weight but the feeling of poor appetite that obviously bothers you. It is hard to give any reasonable advice how to increase appetite when you are on appetite suppressants, actually.

There are several-height charts available, one that calculate the body mass index is here:
http://www.nhlbi.nih.gov/guidelines/obesity/BMI/bmicalc.htm

[Caryopteris]

Avoid caffeine, or any other stimulants, obviously.

I never had any luck eating more when I had loss of appetite, but I suppose you could try drinking a shake with lunch or add nuts as a snack.  The problem is you aren't thinking about food and it's a chore.  

If your doc says your weight is okay, just focus on nutrition, eating vegetables and fruit and nuts and some meat.  You can afford to eat some desserts, but unfortunately you won't really enjoy them.  Avocado is a high fat and very nutritious food to add to salads.