Cough medication sits at the center of this dementia and brain health question.
According to clinical trials, the cough medication that actually works best — particularly for nighttime cough in children — is not a pharmaceutical product at all. It is honey. A landmark 2007 Penn State study of 105 children found that a single dose of buckwheat honey before bedtime provided better relief of nighttime cough than dextromethorphan, the active ingredient in most over-the-counter cough suppressants. Dextromethorphan, meanwhile, was not significantly better than no treatment at all. Lead researcher Dr. Ian Paul called it “the first time honey has been actually proven as a treatment.” For the millions of adults and caregivers navigating pharmacy aisles each cold season, this finding should reshape how we think about cough relief — and it carries particular relevance for older adults and dementia caregivers managing respiratory symptoms in vulnerable populations.
The broader clinical picture is even more striking. The American College of Chest Physicians’ CHEST Expert Panel found no strong evidence to support or refute the use of over-the-counter antitussives, expectorants, mucolytics, antihistamines, or combination products for acute cough. There are currently zero FDA-approved drugs specifically for chronic cough — defined as cough lasting more than eight weeks — despite roughly 100 million patients worldwide living with the condition. Yet cough and cold remedies continue to generate billions of dollars in annual U.S. sales. This article examines what the clinical trial data actually says about common cough treatments, which ingredients have been declared ineffective by the FDA’s own advisors, and what new therapies are moving through the drug pipeline for chronic cough in 2025 and 2026.
Table of Contents
- What Does the Clinical Evidence Say About Common Cough Medications?
- Why Honey Outperforms Pharmacy Cough Syrups in Clinical Trials
- The OTC Cold Aisle Problem — Ingredients That Don’t Work
- What Caregivers Should Actually Reach for When a Cough Won’t Quit
- The Chronic Cough Crisis — Why There Are No Approved Treatments
- New Chronic Cough Drugs in the Pipeline for 2025–2026
- What This Means for Brain Health and Dementia Care Going Forward
- Conclusion
- Frequently Asked Questions
What Does the Clinical Evidence Say About Common Cough Medications?
Most people reach for dextromethorphan when a cough sets in. It has been FDA-approved since 1958 as a centrally acting, nonopioid antitussive, and it remains the backbone of brands like Robitussin DM and Delsym. Clinical evidence shows it is modestly effective in adults with viral upper respiratory infections, but the picture is far from reassuring. Some studies suggest it may be no more effective than placebo for acute coughs, and it has been shown to be ineffective in children. For older adults, especially those with cognitive impairment or dementia, dextromethorphan also carries risks of drowsiness, confusion, and potential drug interactions with common medications like SSRIs — making it a less-than-ideal first choice in that population. Guaifenesin, the expectorant found in Mucinex, works differently. Rather than suppressing the cough reflex, it thins mucus to make coughs more productive.
A 2025 narrative literature review confirmed benefits for managing mucus-related cold symptoms, and one clinical trial found that guaifenesin actually inhibited cough-reflex sensitivity relative to placebo. Interestingly, benzonatate alone did not achieve the same effect in that trial. Still, guaifenesin does not stop coughing — it changes its character. For someone caring for a person with dementia who is coughing through the night, the distinction between suppressing a cough and loosening mucus matters enormously when choosing a treatment approach. Then there is benzonatate, sold under the brand name Tessalon Perles, a prescription cough suppressant that numbs stretch receptors in the lungs. Despite its widespread use, a 2023 systematic review found inadequate evidence to support its effectiveness and flagged rising safety concerns. Most supporting studies are decades old and rated as “very low quality” by modern standards. For older adults with swallowing difficulties — common in mid-to-late stage dementia — benzonatate capsules pose an additional choking hazard, and accidental chewing of the capsule can cause rapid numbing of the mouth and throat.
Why Honey Outperforms Pharmacy Cough Syrups in Clinical Trials
The Penn State study that put honey on the map was not a small or poorly designed trial. Researchers randomly assigned 105 children ages 2 to 18 with upper respiratory infections to receive either a single dose of buckwheat honey, honey-flavored dextromethorphan, or no treatment before bedtime. Parents then rated their children’s cough symptoms. Honey scored significantly better than both dextromethorphan and no treatment on measures of cough frequency, cough severity, and sleep quality. The study was published in the Archives of Pediatrics and Adolescent Medicine, and its findings have been supported by subsequent research. A meta-analysis of two randomized controlled trials encompassing 149 participants found no significant difference between honey and dextromethorphan overall, though one study showed that a 2.5 mL dose of honey had a more alleviating effect on cough caused by upper respiratory infections than dextromethorphan.
The mechanism is not entirely understood, but honey’s viscosity likely soothes irritated throat tissue, and its natural antioxidant and antimicrobial properties may play a role. For dementia caregivers, honey has practical advantages beyond efficacy: it does not cause drowsiness, does not interact with Alzheimer’s medications, and does not require a prescription. However, honey is not appropriate for every situation. It should never be given to children under one year old due to the risk of infant botulism, as warned by the FDA. It is also not a substitute for medical evaluation when a cough persists beyond a few weeks, produces blood, or accompanies fever and shortness of breath. And while the evidence is strongest for nighttime cough from upper respiratory infections, honey has not been rigorously studied for chronic cough conditions or cough related to heart failure, GERD, or ACE inhibitor use — all of which are common in older adults.
The OTC Cold Aisle Problem — Ingredients That Don’t Work
One of the most troubling stories in recent cough and cold medicine history involves phenylephrine, the oral decongestant found in dozens of popular products. An FDA advisory panel declared phenylephrine ineffective as an oral decongestant, calling into question a major ingredient in many over-the-counter cold and cough combination products. This means that for years, consumers have been paying for medications containing an ingredient that does not work at the doses found in store-bought formulations. The decongestant component of products like Dayquil, Sudafed PE, and many store-brand equivalents was essentially a placebo.
This matters for dementia caregivers and older adults because combination cold products — the ones that promise to treat cough, congestion, fever, and sore throat in a single dose — often stack multiple active ingredients, including phenylephrine. These multi-symptom formulations increase the risk of drug interactions, side effects like elevated blood pressure, and confusion in people with cognitive impairment. A person with dementia who takes a nighttime cold formula may experience worsened confusion, urinary retention from antihistamine ingredients, or dangerous blood pressure spikes — all for ingredients whose efficacy has been questioned or outright rejected by the FDA’s own expert panels. The lesson here is straightforward: more ingredients do not mean more relief. Single-ingredient products, used only when a specific symptom warrants treatment, are safer and more rational than combination products — especially in older adults managing multiple chronic conditions and medications.
What Caregivers Should Actually Reach for When a Cough Won’t Quit
For dementia caregivers managing a loved one’s cough, the practical decision tree looks different from what the pharmacy aisle suggests. If the cough is acute — meaning it started with a cold and has lasted less than three weeks — the best first-line approach based on clinical evidence is honey (one to two teaspoons before bed), adequate hydration, and humidified air. This outperformed dextromethorphan in head-to-head trials and avoids the cognitive side effects that make standard cough suppressants risky for people with dementia. If mucus is the primary issue — a wet, productive cough — guaifenesin is the most evidence-supported expectorant and does not typically cause sedation or confusion. It should be taken with plenty of water to work properly.
However, if a cough lasts longer than three weeks, becomes chronic, or is accompanied by weight loss, blood in sputum, or progressive shortness of breath, no over-the-counter product is appropriate. Chronic cough in older adults often signals underlying conditions such as heart failure, GERD, chronic obstructive pulmonary disease, or medication side effects — particularly from ACE inhibitors like lisinopril, which cause a persistent dry cough in up to 15 percent of users. The tradeoff between cough suppression and safety is sharper in dementia care than in the general population. Sedating antihistamines like diphenhydramine, found in nighttime cough formulas, are on the Beers Criteria list of medications to avoid in older adults precisely because they worsen confusion, increase fall risk, and can trigger delirium. A cough that disrupts sleep is miserable, but a fall resulting in a hip fracture is far more dangerous.
The Chronic Cough Crisis — Why There Are No Approved Treatments
Chronic cough — defined as cough lasting more than eight weeks — affects approximately 100 million patients worldwide, and there is currently not a single FDA-approved drug to treat it. This is not for lack of trying. The pharmaceutical industry has invested heavily in developing chronic cough therapies, but the road has been difficult. Merck’s gefapixant, a P2X3 receptor antagonist, was rejected by the FDA twice. The most recent rejection followed an advisory committee vote of 12 to 1 against approval, with the panel citing lack of substantial evidence of effectiveness.
The drug also caused significant taste disturbances — a side effect that made the risk-benefit calculation unacceptable to regulators. This gap in treatment is acutely felt by older adults with chronic cough. In people with dementia, a persistent cough disrupts sleep, increases agitation, interferes with eating and swallowing, and can contribute to behavioral symptoms that caregivers struggle to manage. Without approved chronic cough medications, clinicians often resort to off-label use of gabapentin, low-dose morphine, or speech therapy techniques to manage cough hypersensitivity — approaches that carry their own risks in cognitively impaired patients. For caregivers, this means that a chronic cough often requires a specialist evaluation to identify and treat the underlying cause rather than simply suppressing the symptom.
New Chronic Cough Drugs in the Pipeline for 2025–2026
Two drugs currently in late-stage clinical development may change the chronic cough treatment landscape. GSK’s camlipixant, a highly selective P2X3 receptor antagonist, is being tested in two Phase III trials called CALM-I and CALM-II. Its Phase 2b SOOTHE trial showed a 34.4 percent reduction in cough frequency at 50 mg twice daily, with only 6.5 percent of participants experiencing taste-related adverse events — a major improvement over gefapixant’s taste disturbance problem.
Topline Phase III results are expected in the second half of 2025, with potential FDA approval in the second half of 2026. Meanwhile, Trevi Therapeutics is developing nalbuphine ER, a kappa-opioid agonist and mu-opioid antagonist that has shown the highest efficacy of any drug in the pipeline, with approximately 60 percent cough frequency reduction in trials for chronic cough in idiopathic pulmonary fibrosis patients. If either of these drugs reaches approval, it would represent the first-ever FDA-approved treatment for chronic refractory cough — a milestone for the roughly 100 million patients living without targeted therapy.
What This Means for Brain Health and Dementia Care Going Forward
Cough management in dementia care sits at the intersection of several challenges: limited drug efficacy, heightened medication sensitivity, and the difficulty of assessing symptoms in people who may not be able to describe what they are feeling. As the population ages and the number of people living with dementia grows, the need for safe, effective cough treatments will only increase. The potential approval of camlipixant or nalbuphine ER in 2026 could provide clinicians with tools that work through novel mechanisms without the sedation, confusion, and drug interaction risks of current options. In the meantime, the evidence points clearly toward simpler interventions.
Honey for acute nighttime cough. Guaifenesin for mucus management. A careful review of current medications to identify drugs that cause cough as a side effect. And perhaps most importantly, a willingness to question whether the products lining the pharmacy cough-and-cold aisle are actually doing anything at all — because according to the largest body of clinical evidence available, many of them are not.
Conclusion
The clinical trial evidence on cough medications tells an uncomfortable story. The most widely used over-the-counter cough suppressant, dextromethorphan, is only modestly effective in adults and no better than placebo in some studies. A major decongestant ingredient, phenylephrine, has been declared ineffective by the FDA’s own advisors. Benzonatate lacks adequate evidence of efficacy. And there is not a single FDA-approved drug for chronic cough.
What does work, at least for acute nighttime cough, is honey — a finding supported by randomized controlled trials and head-to-head comparisons with standard medications. For dementia caregivers, these findings carry extra weight. Every medication given to a person with cognitive impairment carries the risk of worsening confusion, increasing fall risk, or interacting with existing prescriptions. The safest and most evidence-based approach is to start with the simplest effective intervention, avoid multi-ingredient combination products, and seek medical evaluation for any cough that persists beyond three weeks. The chronic cough pipeline offers hope for the future, but today the best medicine may already be in your kitchen cabinet.
Frequently Asked Questions
Is honey safe for elderly adults with dementia?
Yes, honey is generally safe for adults of all ages. The botulism warning applies only to infants under one year old. However, for people with diabetes, the sugar content of honey should be factored into their dietary management. If the person has severe swallowing difficulties, thin liquids including honey may pose an aspiration risk and should be discussed with a speech therapist.
Can cough medicines worsen dementia symptoms?
Yes. Many over-the-counter cough products contain sedating antihistamines like diphenhydramine or chlorpheniramine, which are on the Beers Criteria list of medications older adults should avoid. These drugs can cause increased confusion, drowsiness, urinary retention, and fall risk. Dextromethorphan can also interact with SSRIs and other serotonergic medications commonly prescribed in dementia care.
Why is there no FDA-approved drug for chronic cough?
Despite affecting approximately 100 million patients worldwide, chronic cough has proven difficult to treat pharmaceutically. Merck’s gefapixant was rejected twice by the FDA, most recently after an advisory committee voted 12 to 1 against approval, citing insufficient evidence of effectiveness. Two other candidates — camlipixant and nalbuphine ER — are in late-stage trials with potential approval timelines in 2026.
When should a cough in an older adult prompt a doctor visit?
Any cough lasting more than three weeks, producing blood, accompanied by unexplained weight loss, or worsening shortness of breath warrants medical evaluation. In older adults, chronic cough is often caused by treatable conditions like GERD, heart failure, postnasal drip, or medication side effects from ACE inhibitors rather than simple respiratory infections.
Does guaifenesin actually suppress coughing?
Guaifenesin is classified as an expectorant, not a suppressant — it thins mucus rather than blocking the cough reflex. However, a clinical trial found that guaifenesin inhibited cough-reflex sensitivity relative to placebo, suggesting it may have some cough-reducing effect beyond its mucus-thinning action. A 2025 literature review confirmed its benefits for managing mucus-related cold symptoms.
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For more, see National Institute on Aging.
