If you feel a blister on a piercing, there's no need to panic. Piercing blisters are very common, and occasionally show up in the healing process even with meticulous care. Before you begin your treatment, first identify the type of bump you're dealing with, where it is located on your body, and how it got there in the first place. After that, remedies, time, and patience will help you cure your unsightly swelling.
A piercing blister can show up for various reasons. So, just because your friend has "the same issue," doesn't mean your protocol for healing should be the same as hers. Prior to coming up with your plan, figure out if your blister is an abscess, a follicular cyst, or hypotrophic scarring (a bump that forms on the backside of the piercing hole). Abscesses are painful lesions caused by a bacterial infection inside or around the piercing. However, while they sound scary, they are the easiest to treat.
Similarly scary sounding, a follicular cyst is actually just a clogged pore. This puss-filled bump can be caused by to an ingrown hair, or dead skin cells trapped inside a pore next to your piercing. Hypotrophic scarring, however, usually occurs in a cartilage piercing (upper ear or nose) and must be tended to immediately—before it becomes a more permanent keloid scar.
Hypotrophic scarring is caused by a loss of collagen due to trauma in and around the piercing site, and you shouldn't delay treatment if it happens to you. First, size down your jewelry's gauge (with professional guidance, of course) to avoid undue pressure on the wound. Then, perform a daily, gentle oil massage (Rosehip seed oil, which is sold for fairly cheap by The Ordinary is preferred,) to dissolve the blister before it becomes a permanent scar.
Check Your Jewelry
The next step in treating whatever is going on is to make sure your jewelry is up to snuff. Are your studs, hoops, or CBR's (captive bead rings) made of surgical stainless steel, surgical titanium, niobium, or Tygon (a surgical plastic)? If you're not sure, visit your local trusted professional piercing studio. They will help you select a quality item in the perfect gauge for healing your piercing. They'll often change it out for you, too, so there's no reason to do it yourself. Then once it's in, leave it there until your bump is completely healed.
Rotate it occasionally if possible, but only after healing.
Keep It Clean
Cleaning your piercing daily with a mild antibacterial soap is the key to eliminating abscesses or cysts, but sometimes they need a little extra help. That's where salt soaks come in. Sea salt soaks draw out the impurities, clearing the bacterial infection and loosening dead skin cells and dried puss. Simply mix 1/8 teaspoon sea salt with water and soak your piercing blister three times a day until it is completely gone. Salt soaks usually do the trick, but certain boils may call for an herbal compress, like a chamomile tea bag soaked in hot water.
A popular solution used to clean new piercings is H2Ocean, and you should always keep some on hand.
Give it time
Once whatever is wrong with your piercing is completely healed, you then can then change your jewelry to whatever you want. But still, select high-quality jewelry purchased only from a professional shop and let them put it in. If your piercing blister rears its ugly head again, repeat the steps above. Remember—piercings are open wounds, and the healing process can be filled with ups and downs. If your piercing becomes painful, red or hot, or excretes green ooze, go see a doctor for a more aggressive treatment.