This looks most like folliculitis. Acne looks similar.
Are the bumps worse with heavy sweating, or did they start after antibiotics?
Why? The yeast type is more likely with heavy sweating, hot climates, a lot of physical activity, recent antibiotics or corticosteroids, and a weakened immune system. Peer-reviewed review, open access
What helps
If pimple-like bumps do not improve with acne products, a health care provider can check for another cause. Acne medicines and antibiotics can make a fungal folliculitis worse.
Peer-reviewed review, open access
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What the sources say about folliculitis
Folliculitis is inflammation of the hair follicles. Bacteria, viruses or fungi can cause it, and so can things that are not infections, such as drug reactions.
The yeast type is more likely with heavy sweating, hot climates, a lot of physical activity, recent antibiotics or corticosteroids, and a weakened immune system.
Illustration made for this page. The sample answer shows how Skinby words a result: a visual resemblance, not a diagnosis. Skinby never names serious conditions from a photo.