What causes folliculitis barbae and pseudofolliculitis barbae?

Folliculitis barbae and pseudofolliculitis barbae are both skin conditions that can arise from a variety of factors primarily related to hair follicles. The correct answer identifies the main causes of these conditions, which include bacterial or viral infections, irritation from shaving, and ingrown hairs.

Folliculitis barbae typically occurs when hair follicles become inflamed, often due to an infection—most commonly staphylococcal bacteria—following shaving. The irritation caused by shaving, especially with improper techniques, can further exacerbate this condition, leading to the development of red bumps or pus-filled blisters.

Pseudofolliculitis barbae, often referred to as "shaving bumps," is primarily caused by ingrown hairs. When hair curls back into the skin after being shaved, it can cause inflammation and irritation, resulting in bumps that look similar to acne. This is often seen in individuals with curly or coarse hair types.

Understanding the multifaceted nature of these conditions highlights why the first option, which encompasses both infections and ingrown hairs as contributors, is the most comprehensive and accurate answer. Other choices, which focus solely on allergic reactions, stress, or improper shaving techniques on their own, do not fully capture the range