Every winter, your normally quiet office turns into an unpleasant symphony: Dry, barking hacks combine with those wet, chesty coughs and the little, tickling throat-clearings to create a productivity-sapping crescendo.  

But winter bugs aren’t the only things that can leave you whooping. There are many different causes of both acute cough—which lasts 4 weeks or less—and chronic cough, which persists past the 8-week mark. And it’s important to figure out what’s actually behind yours. 

That’s because a cough itself is not a disease—it’s a symptom of something else going on in your body.

“It’s actually a protective mechanism that lungs do to evacuate things that are irritating it, like fluid, mucus, or any kind of airway irritant,” said Dr. Jonathan Parsons, the director of The Ohio State University Multidisciplinary Cough Program.

Here are eight of the most common causes of cough. What’s your reason for wheezing? 

Related: The Better Man Project—2,000+ Awesome Tips on How to Live Your Healthiest Life 

1. Bronchitis (Acute Cough)

The common cold can cause a bit of a dry, tickling cough in addition to other symptoms like runny nose, sore throat, or congestion. But if a cough is your predominant symptom, you might have acute bronchitis.

Acute bronchitis usually causes a wet, productive cough, and it’s common to hack up some colored sputum, or mucus, with it. But color isn’t a surefire way to determine if you’re dealing with something viral or bacterial.

“When you cough up dark brown or blood sputum, it’s concerning for infection,” said Dr. Brandi Newsome, a pulmonologist at the University of South Carolina School of Medicine. “But that doesn’t mean it’s not viral.”

In fact, in the vast majority of cases, acute bronchitis is viral. That means antibiotics won’t do a damn thing. So if your doc wants to prescribe them, ask him to do a sputum culture first.

Related5 Conditions You Shouldn’t Take Antibiotics For

And don’t expect an overnight recovery. According to researchers from the University of Georgia, acute coughs caused by bronchitis and other bugs last an average of 18 days.

2. Pneumonia (Acute Cough)

A productive acute cough—often with discolored or even bloody sputum—is a hallmark of pneumonia, a potentially serious illness that is treated with antibiotics. You might also have a fever, overall fatigue and malaise, shortness of breath, and chills.

Interestingly, though, a cough might not pop up right away. That’s because in some cases, the infection in the lungs can be so dense that you’ll need a few days of antibiotics to work on the bugs before the cough comes through, Newsome said.

You can pick up pneumonia out of the blue, just like a common cold. But you can also develop something called secondary bacterial pneumonia after a viral illness. This might be the case if you’ve been dealing with run-of-the-mill cold symptoms for a few days, but then suddenly begin feeling much worse.

In that case, you may spike a high fever, develop chest pain, or experience other symptoms indicative of pneumonia, Parsons said. Sound like you? You’ll need to see your doc. He or she will probably order a chest X-ray—pneumonia often shows up as a hazy, irregular area in your lungs.

3. ACE Inhibitors (Chronic Cough)

ACE inhibitors are a class of medication used to treat high blood pressure by relaxing your blood vessels and increasing blood flow. Unfortunately, though, when they’re broken down in your body, they increase the amount of a substance called bradykinin, which can trigger your cough reflex.

“This cough is usually worse than just a mere nuisance,” Newsome said. “It’s very dry, hacky, and in fits. It kind of reminds you of whooping cough.”

The weird thing: You can be on the meds for years with no problem, she says. Then you can just start hacking one day.

If that’s the case, your doc will probably cease the ACE inhibitors and start you on a different class of BP meds like ARBs. It can take 3 or 4 weeks for an ACE-inhibitor cough to dissipate after discontinuing the meds.

4. Post-Nasal Drip (Chronic Cough)

One of the most common causes of chronic cough is post-nasal drip, where drainage from your sinuses flows down the back of your throat instead of coming out through the nose. When the drip hits your voice box, it irritates it, which triggers a cough, Parsons said.

It’s easy to tell if you’re having post-nasal drip—you can usually notice the thick, salty stuff rolling back down your throat—but you may not equate that with your cough.

Post-nasal drip can irritate your throat and make it sore, and you’ll probably feel worse at night. That’s because reclining on your back helps your sinuses drain more easily—you might wake up coughing and gagging. You might also wake up in the morning with a sick, unsettled stomach from the drainage making its way down in there.

Coughs from post-nasal drip are often wet-sounding, and you may actually hack some stuff up. But that yellowy stuff isn’t from your lungs—it’s very similar to the snot you’d blow out of your nose.

Post-nasal drip is generally diagnosed clinically, though CT scans of the sinuses may sometimes be used. Treatment is antihistamines, which dry out the drainage.

5. Gastroesophageal Reflux Disease (Chronic Cough)

Gastroesophageal Reflux Disease, or GERD, is another one of the most common causes of chronic cough. But a lot of people might not even know they have the disease, since it can present with just a cough instead of the more typical signs like heartburn or sour stomach, Parsons said. 

In GERD, the acids from your stomach travel up to your esophagus where they reach your voice box. When the acids hit that level, they burn the bottom of your voice box and trigger a reflex for a dry-sounding cough.

People with GERD will often notice an increase in cough after eating a heavy meal. It’s usually also worse at night or first thing in the morning, since lying down allows the acid to move more readily up your esophagus.

Your doctor can look for GERD with a test that measures the amount of acid in your esophagus. He or she may also use a scope, a flexible tube equipped with a camera that’s snaked down your nose to the back of your throat. 

If your doctor suspects GERD, you can make some lifestyle changes to reduce the reflux. This includes limiting or avoiding alcohol, caffeine, late-night eating, and spicy or fatty foods, Parsons said. Your doc may also prescribe an acid reflux medication like Zantac or Prilosec.

Related: The Fastest Cure for Heartburn 

6. Asthma (Chronic Cough)

Asthma, post-nasal drip, and GERD make up the three most common causes of chronic cough. With asthma, the tubes carrying air to your lungs constrict. This often causes things like wheezing and shortness of breath, but it also can spark a dry cough.

In fact, there’s a type of asthma called cough-predominant asthma, in which cough would be the only symptom. More likely, though, you’ll also have some of the more common symptoms. 

“We see patients who notice they’ve had some symptoms when they look back at it,” Newsome said. “They’ll say, ‘Oh, when I was a kid, I couldn’t really run far without being short of breath,’ but nobody diagnosed it then.”

Related: Why Exercise Makes You Cough 

Asthma is typically diagnosed through breathing tests or lung function tests. If tests come back normal, your doc may take it a step further and test the hyperreactivity of your airways, to see if that’s causing your cough. The condition is often treated with a drug called Albuterol or an inhaled steroid.

7. Chronic Obstructive Pulmonary Disease (Chronic Cough)

Chronic obstructive pulmonary disease, or COPD, is a serious cause of chronic cough. COPD is a progressive disease that makes it harder and harder to breathe due to injury to the airways, usually caused by long-term cigarette smoking or exposure to occupational irritants like smoke or dust, Parsons said. 

There are two types of COPD: chronic bronchitis and emphysema.  In chronic bronchitis, the lining of your airways is constantly inflamed. This results in a chronic productive cough. Emphysema gradually damages the air sacs in your lungs, reducing the amount of oxygen that hits your blood. This can cause dry cough, wheezing, and shortness of breath.

COPD is treated similar to asthma, with long-term inhaled steroids and bronchodilators like Albuterol. These meds can help manage symptoms, but there is no cure for the disease—so make sure you stub out those smokes now.

8. Lung Cancer (Chronic Cough)

If you’ve been croaking for more than a few weeks, chances are lung cancer has crossed your mind. It’s not hard to understand the worry: The prognosis for lung cancer remains poor, with only 17 percent of people diagnosed with it surviving 5 years or more.

But this should put your mind at ease: “It’s pretty rare to have an isolated cough as the only symptom to herald a lung cancer,” Parsons said.  “If you really did have lung cancer, it’s unlikely that you are going to be coughing with no other symptoms for more than 8 weeks—you’re going to develop other things.”

That means other related symptoms associated with lung cancer, like weight loss, coughing up blood, fatigue, and chest pain. If that sounds like you, make an appointment with your doc ASAP. He’ll probably order a chest X-ray to see if there are any masses or tumors.

It’s also possible that lung cancer can be mistaken for pneumonia on a chest X-ray, though they usually look quite different. So if you’ve been diagnosed with pneumonia and haven’t responded to multiple courses of antibiotics, you may want to get the procedure repeated to make sure it really is pneumonia, Newsome said. It’s also a good idea to get a follow up X-ray 6 to 8 weeks after treatment in general.

Nonsmokers can get lung cancer, but like COPD, it’s much more common in current smokers and former smokers. So if you’re still lighting up, make 2016 the year you quit for good.

This article originally appeared on MensHealth.com.