Yes, you can absolutely bring your medications in Nepal. Although you can also find proper medication institutions and hospitals in Nepal, you need not be hesitant about your need for medication. The trekking and trip trails also have great availability of clinics and health posts to cater to your needs of health and related services.
Medications to some minor health issues like a headache and diarrhea can also be brought with you, and it is highly recommended that you carry a portable water purifier with you on the trips. You are also advised to consult with your doctor before heading to Nepal.