Breaking out along the jawline or neck is a dead giveaway that hormones are to blame. Dr. Gross says that this is an area where women specifically tend to break out, and that you are more likely to see this type of pimple during the premenstrual phase of your cycle."The T-zone indicates hyperactive oil glands," says Dr. Gross. And as we all know, a surplus of oil on the skin leads to an increase in pore sludge that causes blackheads, which can beget pimples. While this is more commonly seen in teenagers, Dr. Gross says T-zone breakouts usually happen because those areas — the forehead, nose, and chin — are where you have the most oil glands, so there is just a higher chance of them getting plugged up.Genetic acne will usually affect the entire face. If one or more of your parents had bad acne, you can expect to see that same hell on your own face. Thanks, mom. The exception to that rule can be caused by using the wrong products. "[If someone is using] a moisturizer and everywhere that product goes, they break out," Dr. Gross says, "[then odds are] that particular ingredient is making you break out."When Dr. Gross sees new patients with this type of acne, he asks them to bring all of the products they use on their face to their appointment. He then looks at the labels and identifies any possible irritants, and advises patients to eliminate those in their routine. If you don't see an improvement after that, Dr. Gross says, then it's almost certain your acne is genetic. But in order to make that diagnosis, it's important to first systematically go through all of the possible causes.Nine times out of 10, says Dr. Gross, people who only have blackheads on their forehead can thank their hair products for their current misery. "People who only have blackheads on the forehead are usually applying things like leave-in conditioners and waxes," he says. When we put a product on our hair, he explains, we expect it to stay there, when the reality is that our scalps release heat, and that heat can liquify the products and cause them to seep into the skin "like lava flowing down a mountain." The phrase "skin eruptions" seems particularly apt now.All signs point to milia on this one. Those little white bumps are commonly caused by makeup removers, says Dr. Gross, which can cause oil overproduction. May we suggest a micellar water If your blackheads are concentrated around the perioral area (i.e. around the mouth, nose, and lower cheeks), your acne likely isn't actually acne at all — it's a form of rosacea called perioral dermatitis . "Rosacea is a type of rash," notes Dr. Gross, "so it will be treated in a different way than acne." This can include topical antibiotics and anti-inflammation products. But, you have to be a lot more careful with how you treat this breakout. "People with acne have oily skin and it's thicker, so you want to be a bit more aggressive," he says. "Rosacea patients are more sensitive — the [main] component of rosacea is inflammation. It's a rash." So while topical creams, peels , and lasers can help minimize the outbreaks, they have to be much gentler than traditional acne protocols.The above categories are in no way true for all patients. No one acne case is the same, which is why it is important to go to your doctor for a final diagnosis, and to be sure your blackheads and bumps aren't caused by a more serious health issue like PCOS (polycystic ovary syndrome). But next time you look in the mirror and curse at your blackheads, pay close attention to where they are clustering — the answer to your complexion conundrum might be staring you right in the face.