How can a hyperthyroid patient gain weigh?

I'm a hyperthyroid patient.It causes me to loss weigh(actually I'm always this thin).Is there any drug,exercise or any form of treatment to overcome it.My details:


a)Gender:male


b)Age:14


c)Height:5'6(173cm)





Actually,my condition is quite minor,I don't have typical symptoms of hyperthyroid such as hair losing and sweating.I really appreciate your helpful information,thanks.How can a hyperthyroid patient gain weigh?
eat more fat!