The fastest way to get rid of phlegm is to thin it out so your body can clear it naturally. Drinking warm fluids, using steam, and learning a specific breathing technique called the huff cough can loosen and move phlegm within minutes. For persistent congestion, an over-the-counter expectorant or honey can speed things along.
Phlegm is mucus produced in your lower respiratory tract, typically thicker than the mucus in your nose or sinuses because it’s actively trapping and fighting off infection or irritants. Your body makes it for a reason, so the goal isn’t to stop production entirely. It’s to thin it, move it up, and get it out.
Drink Warm Fluids Throughout the Day
Staying well-hydrated is the single most effective thing you can do to thin phlegm. When your body is even mildly dehydrated, mucus thickens and becomes harder to cough up. Warm liquids work better than cold ones because heat helps break down the gel-like structure of mucus. Hot water with lemon, herbal tea, and broth are all good choices. Coffee and alcohol can dehydrate you, so they’re not ideal substitutes.
There’s no magic number of glasses to hit, but if your urine is dark yellow, you’re not drinking enough. Aim to sip steadily rather than downing large amounts at once.
Use Steam to Loosen Congestion
Inhaling steam delivers warm moisture directly to your airways, softening thick phlegm so it moves more easily. You can take a hot shower, run a hot bath with the bathroom door closed, or lean over a bowl of hot water with a towel draped over your head. Five to ten minutes is enough per session.
A humidifier in your bedroom can also help, especially overnight when mouth breathing dries out your airways. Keep indoor humidity between 30% and 50%. Going above 50% encourages mold and dust mites, which can make congestion worse. Clean your humidifier regularly to prevent bacteria from building up inside it.
Try the Huff Cough Technique
Hard, forceful coughing can actually trap phlegm deeper by collapsing the smaller airways. The huff cough is a technique used in respiratory therapy that moves mucus outward without that collapse. It works faster than regular coughing for most people, and you can do it anywhere.
- Sit upright in a chair or on the edge of your bed with both feet flat on the floor. Tilt your chin up slightly.
- Breathe in slowly until your lungs feel about three-quarters full.
- Exhale in short, forceful bursts with your mouth open, like you’re trying to fog up a mirror. These are smaller and sharper than a full cough.
- Repeat one or two more times, then follow with one strong, deep cough to push the loosened mucus out of the larger airways.
Do two or three rounds depending on how congested you feel. This technique is especially useful first thing in the morning when phlegm has pooled overnight.
Use Gravity to Drain Your Lungs
Postural drainage uses body positioning to let gravity pull mucus out of different parts of your lungs. You might lie on your stomach, your side, or your back, or prop yourself up at an angle. Each position targets a different area. Lying on your stomach with a pillow under your hips, for example, helps drain the lower lobes of your lungs. Lying on one side clears the opposite lung.
Stay in each position for five to ten minutes, breathing slowly. Combining postural drainage with the huff cough technique makes both more effective. This is a standard approach used in physical therapy for people with chronic lung conditions, but it works just as well for a bad chest cold.
Try Honey Before Bed
Honey coats the throat and has mild antimicrobial properties that can calm the cycle of coughing and phlegm production, particularly at night. A study published in The Journal of Pediatrics found that a single dose of buckwheat honey before bedtime reduced cough severity by 47% compared to 25% with no treatment. It performed as well as the common cough suppressant dextromethorphan, which itself did no better than doing nothing at all.
One to two teaspoons of raw honey, taken straight or stirred into warm water or tea about 30 minutes before sleep, is a simple and effective option. Do not give honey to children under one year old due to the risk of infant botulism.
Gargle With Salt Water
A salt water gargle draws moisture out of swollen throat tissue through osmosis and helps loosen phlegm clinging to the back of your throat. Dissolve roughly half a teaspoon of table salt in 8 ounces of warm water. Gargle for 15 to 30 seconds, spit it out, and repeat a few times. You can do this several times a day.
This won’t reach phlegm deep in your lungs, but if most of your discomfort is in the throat or the sensation of mucus dripping down the back of your nose, it provides quick relief.
Over-the-Counter Expectorants
Guaifenesin is the active ingredient in most OTC expectorants. It works by thinning mucus in the lungs so you can cough it up more easily. The standard adult dose is 200 to 400 milligrams every four hours for regular tablets, or 600 to 1,200 milligrams every twelve hours for extended-release versions. Drink a full glass of water with each dose to help it work.
Avoid combining an expectorant with a cough suppressant unless your doctor has specifically recommended it. Suppressing the cough reflex while thinning mucus defeats the purpose, since the whole point is to get the phlegm moving and out.
What Phlegm Color Actually Tells You
Many people assume that green or yellow phlegm means a bacterial infection that needs antibiotics. This is a common myth, even among some clinicians. Both viral and bacterial infections cause the same color changes in mucus. The color comes from white blood cells and enzymes your immune system releases during any infection, not specifically from bacteria.
A more reliable signal is timing. With a viral infection, phlegm often starts clear and turns colored several days in. With a bacterial infection, thick, colored mucus tends to appear earlier. Bacterial infections also tend to last more than 10 days without improvement, or follow a pattern where symptoms get better and then suddenly worsen again.
Signs That Need Medical Attention
Most phlegm from a cold or mild respiratory infection clears within two to three weeks. Seek care if your cough persists beyond that or comes with wheezing, fever, shortness of breath, fainting, ankle swelling, or unexplained weight loss. Coughing up blood or pink-tinged phlegm, difficulty breathing or swallowing, or chest pain all warrant emergency evaluation.