Of course. Along the way there are many opportunities to stop at a facility when nature calls. When you first begin the trek, the bathroom facilities are managed by locals and you need to pay to use them. A sole will grant you entry and the bathrooms are generally clean.
By the time you leave lunch the first day, you will notice the bathroom conditions start to deteriorate. You will no longer need to pay for the facility, but you will have to deal with piles of dirty tissue. The later in the day you use the facility, the worse the condition will be.
All the toilets are squatters and you are not allowed to flush any paper – which is fine since they rarely offer you any paper – make sure to have some on you. There are often bins in the bathroom that you are meant to leave your dirty paper in. Bathrooms are not regularly cleaned and the paper quickly builds up. Once full, people start throwing the tissue anywhere on the ground, where it ends up piling around where you are meant to have your feet.