For the common cough that comes with a cold, honey is one of the best-supported options, performing at least as well as the most popular over-the-counter cough suppressant in head-to-head comparisons. That answer surprises most people, because pharmacy shelves are packed with products that seem more serious. But the evidence behind many of those products is thinner than you’d expect, and the “best” thing to take depends heavily on what is making you cough in the first place.
Why the Cause of Your Cough Matters
Cough is broadly classified by how long it has been going on. A cough lasting less than three weeks is considered acute and is almost always caused by a respiratory infection, usually viral. A cough lasting three to eight weeks is called subacute and is typically the tail end of that same infection. A cough that persists beyond eight weeks is chronic, and the list of possible causes expands dramatically: postnasal drip from sinus problems, asthma, acid reflux, and a variety of rarer conditions all enter the picture.1PubMed Central. Classification of Cough as a Symptom in Adults and Management Algorithms: CHEST Guideline and Expert Panel Report Chronic cough affects roughly one in ten people and is one of the most common reasons for a doctor’s visit.2PubMed Central. Chronic Cough
This matters for treatment because a remedy that soothes an acute viral cough does nothing for a cough driven by acid reflux, and a proton pump inhibitor does nothing for postnasal drip. Most of the remedies discussed below target acute cough from upper respiratory infections, since that is what sends most people to the pharmacy. If your cough has lasted more than eight weeks, skip to the chronic-cough sections below and talk to a doctor.
Dextromethorphan and Codeine
Dextromethorphan, usually labeled “DM” on cough-syrup packaging, is the most widely used over-the-counter cough suppressant. The evidence for it is genuinely mixed. A systematic review of randomized controlled trials in adults found conflicting results when comparing antitussives, expectorants, and combination products to placebo.3PubMed Central. Systematic review of randomised controlled trials of over the counter cough medicines for acute cough in adults One well-designed adult trial reported that a single 30-mg dose of dextromethorphan showed “very little if any support for clinically significant antitussive activity” compared with placebo in people with acute upper respiratory infections.4Journal of Pharmacy and Pharmacology. Antitussive Efficacy of Dextromethorphan in Cough Associated with Acute Upper Respiratory Tract Infection On the other hand, a pediatric trial in children aged six to eleven found that dextromethorphan reduced 24-hour cough counts by about 21% relative to placebo, a result the authors considered both statistically significant and medically relevant.5PubMed. Objective and self-reported evidence of dextromethorphan antitussive efficacy in children, aged 6-11 years, with acute cough due to the common cold
So dextromethorphan probably does something, but the effect is modest and inconsistent across studies. It is not the dramatic cough silencer that many people imagine when they reach for a bottle of cough syrup.
Codeine has an even worse track record. Long considered the gold standard prescription cough suppressant, recent placebo-controlled studies show it is no more effective than placebo for cough caused by upper respiratory infections or chronic obstructive pulmonary disease.6PubMed Central. Codeine and cough: an ineffective gold standard A Cochrane review confirmed this, finding codeine no better than placebo at reducing cough symptoms.7Cochrane Database of Systematic Reviews. Oral over-the-counter cough preparations for acute cough in children and adults Given that codeine carries real risks of sedation, constipation, and dependence, its continued use for cough is hard to justify on the evidence.
Honey
Honey has more consistent evidence behind it than most pharmacy cough products, particularly for children. A systematic review and meta-analysis published in BMJ Evidence-Based Medicine found that honey reduced cough frequency and cough severity compared with usual care, with pooled results showing meaningful improvements across multiple studies.8PubMed. Effectiveness of honey for symptomatic relief in upper respiratory tract infections: a systematic review and meta-analysis A separate systematic review focused on children found low-quality but consistent evidence that honey may be more effective than cough medication or placebo at relieving symptoms and improving sleep.9PubMed Central. Honey for acute cough in children – a systematic review
One of the more cited studies in this area directly compared honey, dextromethorphan, and no treatment in coughing children. Parents rated honey as producing the greatest improvement across every outcome measured: cough frequency, cough severity, sleep quality for both child and parent, and a combined symptom score. Honey outperformed no treatment by a wide margin, and although the direct comparison between honey and dextromethorphan did not reach statistical significance, honey consistently scored higher on every measure.10Archives of Pediatrics & Adolescent Medicine. Effect of Honey, Dextromethorphan, and No Treatment on Nocturnal Cough and Sleep Quality for Coughing Children and Their Parents
The important caveat: never give honey to children under one year of age because of the risk of infant botulism. For everyone else, a spoonful of honey before bed is a reasonable first-line approach for an acute cough, and the World Health Organization and multiple national guidelines mention it as an option.
Guaifenesin for Wet, Mucusy Coughs
If your cough is productive, meaning you’re bringing up phlegm, the question shifts from “how do I stop coughing” to “how do I get the mucus out more easily.” Guaifenesin is the only legally marketed expectorant in the United States and is found in products like Mucinex and Robitussin. It works by reducing mucin production and decreasing the thickness of mucus, which allows your airway cilia to move secretions upward more effectively.11PubMed. Effect of guaifenesin on mucin production, rheology, and mucociliary transport in differentiated human airway epithelial cells Lab studies show this mechanism clearly, and the drug has FDA recognition for loosening phlegm and thinning bronchial secretions.12PubMed Central. Role of guaifenesin in the management of chronic bronchitis and upper respiratory tract infections
The gap between the lab evidence and the clinical evidence is worth noting, though. A comprehensive review acknowledged that published evidence of guaifenesin’s clinical efficacy, particularly in chronic bronchitis, remains limited.13PubMed Central. The Role of Guaifenesin in the Management of Chronic Mucus Hypersecretion Associated with Stable Chronic Bronchitis: A Comprehensive Review It likely does thin mucus, but whether that reliably translates to fewer coughs and faster recovery in real patients is less certain than the packaging suggests. Staying well hydrated does something similar for free.
Menthol, Syrups, and the Soothing Effect
If you’ve ever noticed that simply taking a spoonful of cough syrup makes you feel better before the active ingredient could possibly have kicked in, you’ve experienced something researchers take quite seriously. The act of swallowing a sweet, viscous liquid stimulates saliva production and mucus secretion in the throat, coating and lubricating irritated airways. This physiological soothing effect is a real contributor to how liquid cough medicines work, and it is largely absent when the same drug is taken as a tablet.14PubMed Central. The Powerful Placebo Effect in Cough: Relevance to Treatment and Clinical Trials This may help explain why honey, essentially a thick sweet liquid, performs so well.
Menthol adds another layer. The cooling sensation you feel from menthol lozenges or vapor rubs is not just a distraction. Menthol activates a cold-sensitive receptor called TRPM8 in nerve fibers in the nose and upper airways. In guinea pig studies, menthol vapors delivered to the upper airways suppressed cough triggered from lower in the respiratory tract, but menthol applied directly to the lower airways had no effect. The antitussive action appears to be a reflex initiated from the nose, not a direct numbing of the cough trigger site.15PubMed Central. The role of trigeminal nasal TRPM8-expressing afferent neurons in the antitussive effects of menthol A review of plant-derived substances in cough remedies confirmed that menthol activates TRPM8 and may inhibit respiratory reflexes, reducing the urge to cough.16PubMed Central. Modulation of transient receptor potential (TRP) channels by plant derived substances used in over-the-counter cough and cold remedies So menthol lozenges and inhaled vapors are not just folk medicine. They work through a specific pathway, even if the effect is mild.
Cough Medicine and Young Children
Parents of young children face tighter constraints. In 2008, the FDA issued a public health advisory recommending that over-the-counter cough and cold medicines not be used in children under two years of age because of the risk of serious, potentially life-threatening side effects.17PubMed Central. Physician and Parent Response to the FDA Advisory About Use of Over the Counter Cough and Cold Medications Most pediatric guidelines now extend caution to children under six, with many recommending honey (for those over twelve months), fluids, and comfort measures rather than OTC drugs. In the survey following the FDA advisory, the vast majority of parents of children under two reported they would stop using these products.17PubMed Central. Physician and Parent Response to the FDA Advisory About Use of Over the Counter Cough and Cold Medications
For older children, the dextromethorphan data cited above showed a modest effect in children aged six to eleven. But even there, honey performed just as well or better in the direct comparison studies. If your child is over one year old and coughing at night, a half-teaspoon to a teaspoon of honey before bed is a well-supported starting point.
When Medication Is Causing the Cough
Sometimes the best thing to take for a cough is nothing new. Instead, the answer is to stop something you’re already taking. ACE inhibitors, a widely prescribed class of blood pressure medication, cause a persistent dry cough in roughly 2% to 11% of people who use them.18PubMed Central. ACEI-induced cough: A review of current evidence and its practical implications for optimal CV risk reduction The cough develops because ACE inhibitors block the breakdown of certain substances in the airways, leading to irritation. If you have developed a new dry cough after starting a blood pressure drug, mention it to your doctor. Some people can successfully re-challenge with the same medication after a break, while others may need to switch to an alternative class of drug, typically an angiotensin receptor blocker, which does not have the same cough problem.19PubMed. Pathophysiology of cough with angiotensin-converting enzyme inhibitors: How to explain within-class differences? No cough syrup will fix a drug-induced cough. Identifying and addressing the cause is the only effective treatment.
Chronic Cough and Reflux
For coughs that drag on beyond eight weeks, the treatment landscape changes. The most common culprits in nonsmokers with a normal chest X-ray are upper airway cough syndrome (postnasal drip), cough-variant asthma, and gastroesophageal reflux disease.1PubMed Central. Classification of Cough as a Symptom in Adults and Management Algorithms: CHEST Guideline and Expert Panel Report Treating the underlying condition generally resolves the cough. For postnasal drip, first-generation antihistamine-decongestant combinations often work. In one study, about 72% of patients with chronic postnasal drip responded positively to this approach.20PubMed Central. Clinical Aspects of Chronic Idiopathic Postnasal Drip: An Entity Not to Be Overlooked
Reflux-related cough is trickier. A CHEST expert panel report found that proton pump inhibitors alone showed no benefit for reflux-associated cough. The studies with the best cough outcomes were those that included diet modification and weight loss.21Chest. Evidence-Based Medicine Chronic Cough Due to Gastroesophageal Reflux in Adults: CHEST Guideline and Expert Panel Report The panel also noted a strong placebo effect in reflux-cough trials, which makes the evidence particularly difficult to interpret. If your doctor suspects reflux is driving your cough, lifestyle changes should be part of the plan from the start.
Speech Therapy for Stubborn Coughs
One of the more unexpected treatments for chronic cough that won’t respond to standard therapy is a combined physiotherapy and speech and language therapy program. Patients learn breathing techniques, laryngeal hygiene, and cough suppression strategies. A randomized controlled trial found that this intervention reduced objective cough counts by about 41% compared with a control group, along with meaningful improvements in cough-related quality of life.22Thorax. Physiotherapy, and speech and language therapy intervention for patients with refractory chronic cough: a multicentre randomised control trial The improvements within the therapy group were sustained for up to three months.23PubMed Central. Speech and language therapy for management of chronic cough For people who have been coughing for months or years without relief from medications, this kind of behavioral approach is an option that rarely gets mentioned.
New Drugs on the Horizon
For people with refractory chronic cough, meaning the kind that persists despite treating every identifiable cause, a new class of drugs targeting a receptor called P2X3 has been generating results that the cough field hasn’t seen in decades. The most advanced of these is gefapixant. An early crossover trial found that a P2X3 antagonist reduced cough frequency by about 75% compared with placebo in patients with refractory chronic cough.24The Lancet. Efficacy of a P2X3 receptor antagonist, AF-219, in refractory chronic cough: a randomised, double-blind, placebo-controlled, crossover trial A phase 2b dose-ranging trial showed that gefapixant at the highest tested dose significantly reduced cough frequency after twelve weeks.25The Lancet Respiratory Medicine. Gefapixant, a P2X3 receptor antagonist, for the treatment of refractory or unexplained chronic cough: a randomised, double-blind, placebo-controlled, phase 2b trial
Phase 3 results have tempered that initial excitement somewhat. In two large trials, the higher dose of gefapixant (45 mg twice daily) did significantly reduce 24-hour cough frequency versus placebo, but the magnitude of the effect was more modest than earlier trials suggested: around a 15-19% reduction.26The Lancet. Efficacy and safety of gefapixant, a P2X3 receptor antagonist, in refractory chronic cough and unexplained chronic cough (COUGH-1 and COUGH-2): results from two double-blind, randomised, parallel-group, placebo-controlled, phase 3 trials A notable side effect is taste disturbance, which affected a significant portion of participants at the higher dose. Gefapixant has been approved in some countries for refractory chronic cough, and it represents a genuinely new mechanism for a condition that previously had almost no targeted drug options. Whether the benefit-to-side-effect tradeoff is acceptable depends on how severely the cough affects your life.
Pelargonium Sidoides, a Herbal Extract Worth Knowing About
One herbal product has better clinical trial data behind it than most: an extract from the roots of Pelargonium sidoides, a South African geranium species, sold in many countries under the brand name Umckaloabo or as “EPs 7630.” A meta-analysis of randomized, placebo-controlled trials found that in children and adolescents with acute bronchitis, about 80% of those treated with the extract showed at least a 50% reduction in cough intensity, compared with roughly 41% on placebo. In adults with acute bronchitis, the numbers were about 89% versus 48%.27PubMed Central. Effects of Pelargonium sidoides extract EPs 7630 on acute cough and quality of life – a meta-analysis of randomized, placebo-controlled trials A separate randomized trial in children with uncomplicated upper respiratory infections also found meaningful symptom improvement, including cough frequency, within the first three days of treatment.28PubMed. Effectiveness of Pelargonium sidoides in pediatric patients diagnosed with uncomplicated upper respiratory tract infection: a single-blind, randomized, placebo-controlled study
This extract is more widely known in Europe and parts of Africa than in the United States. It is not a miracle cure, and the effect sizes are moderate. But for a herbal product to have multiple placebo-controlled trials behind it is unusual, and it may be worth considering if you prefer to avoid conventional cough medicines or have found them unhelpful. It is generally well tolerated, though people with bleeding disorders or those on blood thinners should consult a doctor before use.
Steam, Humidity, and Fluids
Inhaling warm, humid air is one of the oldest cough remedies in existence. A Cochrane review of heated, humidified air for the common cold found uncertain results, with one statistical approach showing a benefit and another showing no significant difference from placebo.29Cochrane Database of Systematic Reviews. Heated, humidified air for the common cold In practical terms, a hot shower or bowl of steam may temporarily loosen mucus and soothe irritated airways, but don’t expect it to shorten your illness. It is safe, free, and can provide momentary relief, which is about all you can ask of most acute cough treatments. Drinking plenty of fluids serves a similar role by helping thin secretions, even though no landmark trial has quantified exactly how much extra water reduces coughing. Given how low the risk is, staying hydrated remains standard advice for a reason.