Cysts and nodules
Clogged pores can swell a lot and eventually cause an infection which gets deep into the skin. The resulting swelling can be very hard and painful (nodules) or they can have a white color and contain pus (cyst). If your face is covered with this type of pimples we recommend you to visit a doctor in order to avoid possible scars that can remain after a wrong treatment.
Pustules and papules
There are times when the clogged pores become so chafed that their surface gets rubbed. As a consequence, large pimples appear on the skin, usually known as pustules and papules.
The difference between the two is that pustules have a yellow color and contain a fluid with the same components with the one found in blisters, whereas papules have a hard consistence, giving you the impression that your skin is like sandpaper, if in the same place there are various pimples.