Four skin factors that lead to acne

1. Clogged pores: Normally, skin cells are in a constant state of gradual renewal. As old cells die, they mix with your skin's natural oils and are sloughed off, making room for fresh, new skin every 30 days. However, this process of shedding dead cells doesn't always happen as it should. Sometimes, the skin cells don't shed evenly or the cell turnover slows down. When that happens, skin cells become "sticky." When they combine with the natural oils of your skin, they clog your pores. A plug called a comedo is formed inside the hair follicle and acts like a cork on a bottle. This plug traps oil and bacteria in the follicle.
2. Overproduction of oil (sebum): Hormones stimulate oil production in the sebaceous glands, which are attached to hair follicles. Normally, the oil flows freely to the surface of your skin. If your hormones tell your sebaceous glands to pick up production, they'll churn out sticky oil, which results in potentially clogged pores that then create an environment for the growth of bacteria.
3. Bacterial attack: Once your pores are clogged, bacteria that is normally growing on your skin starts feeding on the trapped oil. Like all bacteria, it feeds on the oxygen-free atmosphere and moisture. It digests the entrapped sebum, breaking the oil molecules down into smaller particles. When these broken-down oil molecules leak outside the follicle, it generates a response in your body.
4. Inflammation: The body's response to  any proliferation of bacteria is to send an army of red and white blood cells to fight the infection. These cells attempt to wall off the follicle, with the result being the swelling, inflammation and pain that we call pimples.

The different types of acne, or comedones

Although all acne starts the same way, the lesions produced look different on your skin.

Whiteheads: If the plug stays below the surface of the skin, it's called a closed comedo, or a whitehead. The white debris is trapped sebum and dead white blood cells.

Blackheads: If a plug enlarges and widens the pore, it's called an open comedo, or blackhead. Blackheads are not caused by trapped dirt, even though that's what they look like, and you can't simply wash them away. The black spots are from a buildup of melanin, the pigment that colors your skin, and oxidized oil.

Papules: These types of acne are small, pink, domed bumps that are tender to the touch.

Pustules: These are small, round, pus-filled lesions. They appear swollen and red at the base, with a yellowish to whitish center.

Nodules and Cysts: These are large, deep and painful bumps filled initially with blood, then with pus. Persistent nodules can harden into deep cysts, and both may leave deep scars.

These skin professionals will obtain a complete history and carefully examine the affected areas. They'll note the color, number and size of outbreaks. The acne may consist of a field of small, white bumps called whiteheads. These will often disappear on their own. Blackheads form when the material reaches the surface, where it combines with air to form the characteristic dark color. These two are called, respectively, closed or open comedones. A good antibacterial cleanser and time may be all that's needed. In the more severe cases, where nodules or cysts form, the patient may have other symptoms we don't commonly associate with acne, such as fever and aching joints, or even headaches and GI (gastrointestinal) distress. These indicate more serious types of acne, calling for more specialized treatments, such as prescription drugs or lasers.

When symptoms appeared, and in what order, is important. Typically, only the patient can provide that information. It's useful to keep track by keeping a log. Note what type of lesion occurred before the appearance of any pustules and when. Along the way the dermatologist will, naturally, attempt to rule out any alternative explanations. Certain insect bites, such as mosquito or spider bites, can temporarily resemble acne. Mosquito bite lesions, left alone, will disappear in a day or two for all but those who are allergic. Spider bites are often harmless, but some may be poisonous and lesions can spread. That calls for entirely different treatment from acne. Rosacea is a common skin disorder that differs from acne in several respects, but still forms papules and red pustules. Keratosis pilaris produces small bumps that may resemble whiteheads. Miliaria rubra, or heat rash, produces small red bumps. All of these would call for very different treatment from acne. Similarly, many allergies can produce skin lesions, redness and many other symptoms similar to acne. Sexually transmitted diseases are a common ailment. Sometimes they actually produce acne, but they can cause other skin problems, too. Herpes, for example, may show up as red, painful bumps on the buttocks.

Certain drugs can actually cause acne. Anabolic steroids, lithium and prednisone, are common today. Phenobarbital and tetracycline can cause acne. Dermatologists will require a complete and honest history of drug use in order to make a proper diagnosis. Sometimes, even excess use of Vitamin B complex can cause acne.

The doctor will need to know about diet, supplements and whether any over the counter medications or remedies have already been tried. Knowing as much as possible about your own skin and the history of any outbreaks will aid proper diagnosis. That, it should go without saying, is key to any proper treatment.

Now, there are many more effective treatment options available. Understanding acne and how it can be treated is the first step in having the kind of skin you want - free of blemish.

What is acne?

Acne is a common skin disease that results when pores get blocked and bacteria form inside them. It comes in a variety of familiar forms and affects nearly everyone at some stage, particularly in their teen years. The inflamed, red bumps that sometimes form can be painful, and even painless white pimples are unsightly.

In the surface of the skin are pores, tiny openings called a hair follicle. Deeper inside the pore, near the base of the follicle, there are sebaceous glands that produce sebum, a natural type of oil. That oil helps keep the skin flexible and protected.

Hair continues to grow through the surface, while oil or sebum oozes out the side and is spread around the area. Skin cells grow and die and are sloughed off through washing, rubbing or spontaneously. But that process can be interrupted when the pores close and when bacteria form inside them. The result is acne.

The white pimples that sometimes form are usually a combination of dead skin cells, white blood cells and bacteria. The trapped pus often creates an inflamed, red area around it. The term 'pus' is an adaptation of 'pustule', a type of acne that results when the follicle wall bursts and the white blood cells rush into the area as part of a healing process.

When the tiny bumps or spots appear black they're called blackheads, naturally enough. They're a non-inflamed form of acne that come from the material having poked through the surface. Their dark color isn't the result of contact with dirt on the skin. It's a combination of dead skin cells and sebum that have oxidized. Oxygen in the air causes a chemical reaction that turns them black.

Often, however, the material doesn't break the skin, but simply pushes it up, forming a small, white bump called whiteheads. One form are known as 'milia'. Normally dead skin cells will get washed off or simply fall off the surface. But they can get trapped underneath the surface. This type of acne is common among infants, but can affect people at any age.

All these variations go by a general medical term called 'comedones', and whether that formation is open or closed is part of the clinical difference between them.

As the acne develops it can variously form what are called papules, nodules or cysts. A papule forms when the walls holding the hair follicle burst near the surface. They're small and don't contain pus. A nodule is a hardened lump under the skin, resulting from a break at the base of the follicle. A cyst is a larger, reddened bump. They're soft, but can be very painful.

Naturally, while it's helpful to know what acne is, the most important thing is to be able to treat it. In order to do that, it's necessary to know what type we have. We hope you find the information you need here to help you determine the type of acne you have and the best treatment options.