Most upper respiratory tract infections are caused by viruses, which means the majority of medications used to treat them are aimed at relieving symptoms rather than curing the infection itself. Prescription antivirals exist for influenza and COVID-19, but for the garden-variety cold or viral sore throat, you’re working with a toolkit of decongestants, pain relievers, cough suppressants, and a handful of supplements with varying degrees of evidence behind them. Choosing the right options and avoiding the wrong ones matters more than most people realize, because some popular products barely outperform a sugar pill, and common dosing mistakes can cause real harm.
Why Antibiotics Usually Don’t Help
Acute respiratory infections are the single most common reason antibiotics get prescribed to adults, yet the vast majority of these prescriptions are unnecessary. The American College of Physicians and the CDC have jointly issued guidance stating that antibiotics are often inappropriately prescribed for these conditions in otherwise healthy adults without chronic lung disease or compromised immune systems.1PubMed. Appropriate Antibiotic Use for Acute Respiratory Tract Infection in Adults: Advice for High-Value Care From the American College of Physicians and the Centers for Disease Control and Prevention A large descriptive study of primary care encounters found that antibiotics were unnecessarily prescribed in roughly 42% of visits for conditions like acute bronchitis, sinusitis, and nonspecific upper respiratory infections.2PubMed Central. Antibiotic Prescribing Practices for Upper Respiratory Infections Among Primary Care Providers: A Descriptive Study
Distinguishing a bacterial infection from a viral one by symptoms alone is unreliable. Research into blood markers like C-reactive protein (CRP) shows promise, and a rapid test called FebriDx that combines CRP with a viral marker called MxA can deliver results in about ten minutes, potentially helping clinicians decide whether antibiotics are warranted.3Clinical Infectious Diseases. A Rapid Test to Differentiate Viral From Bacterial Infections: Searching for the Holy Grail Still, the practical reality for most people with a runny nose, cough, and sore throat is that the infection is viral, and the focus should be on managing symptoms while the body clears the virus.
Oral Decongestants and the Phenylephrine Problem
If you’ve ever taken an over-the-counter cold pill for nasal congestion and felt like it did nothing, you may have been taking oral phenylephrine. A controlled study comparing phenylephrine, pseudoephedrine, and placebo found that phenylephrine performed no better than placebo at relieving nasal congestion over a six-hour observation period, while pseudoephedrine was significantly more effective than both.4PubMed. A placebo-controlled study of the nasal decongestant effect of phenylephrine and pseudoephedrine in the Vienna Challenge Chamber A systematic review of the broader literature on oral phenylephrine reached the same conclusion: it consistently failed to beat placebo.5PubMed Central. The Use and Efficacy of Oral Phenylephrine Versus Placebo Treating Nasal Congestion Over the Years on Adults: A Systematic Review
This is worth knowing because after pseudoephedrine was moved behind the pharmacy counter in the United States (due to its use in methamphetamine production), phenylephrine became the default decongestant in many brand-name cold products sitting on open shelves. The FDA’s advisory committees have revisited the question and acknowledged the evidence against oral phenylephrine, but many products still contain it as the sole decongestant. If you want an oral decongestant that actually works, look for pseudoephedrine and ask for it at the pharmacy counter.
Pseudoephedrine does come with caveats. A meta-analysis found it causes a small but measurable bump in systolic blood pressure (around 1 mmHg on average) and a slight increase in heart rate (about 3 beats per minute), with bigger effects at higher doses and with immediate-release formulations.6Archives of Internal Medicine. Effect of Oral Pseudoephedrine on Blood Pressure and Heart Rate: A Meta-analysis For most healthy people that’s trivial, but rare serious cardiovascular events, including hypertensive crises and stroke, have been documented with sympathomimetic decongestants, especially when they’re overused or combined with other stimulating drugs.7PubMed. Cardiovascular and Cerebrovascular Events Linked to Abuse and Misuse of Sympathomimetic Nasal Decongestants: A Narrative Review of Clinical Evidence If you have high blood pressure or heart disease, talk to a pharmacist before reaching for any decongestant.
Nasal Spray Decongestants and Rebound Congestion
Topical sprays containing oxymetazoline or xylometazoline work far more reliably than oral phenylephrine. They shrink swollen nasal tissue within minutes by stimulating receptors on blood vessels inside the nose. The catch is that using them for too long creates a cycle of dependence. In a study of healthy volunteers who used oxymetazoline spray three times daily, no rebound swelling was observed after ten days, but after thirty days every participant developed rebound congestion and reported nasal stuffiness.8ORL. Decongestion Effect and Rebound Swelling of the Nasal Mucosa during 4-Week Use of Oxymetazoline
The mechanism behind this rebound involves the nose’s blood vessels losing their responsiveness to the drug over time. With prolonged exposure, the receptors that trigger vasoconstriction become less sensitive, and the nasal lining swells more than it did before you started spraying.9European Annals of Otorhinolaryngology, Head and Neck Diseases. Rebound congestion and rhinitis medicamentosa: Nasal decongestants in clinical practice. Critical review of the literature by a medical panel The standard advice is to limit nasal decongestant sprays to no more than three to five days. Using them judiciously for the worst nights of a cold is reasonable; making them a daily habit is not.
First-Generation Versus Second-Generation Antihistamines
Antihistamines are a staple of multi-symptom cold products, but not all antihistamines help with colds equally. Older, first-generation antihistamines like chlorpheniramine and diphenhydramine do reduce sneezing and runny nose during a cold. Newer, second-generation antihistamines like loratadine and cetirizine, despite being better tolerated and less sedating, have been ineffective at suppressing sneezing in people with colds in multiple studies.10Clinical Infectious Diseases. Variant Effect of First- and Second-Generation Antihistamines as Clues to Their Mechanism of Action on the Sneeze Reflex in the Common Cold
The reason appears to be that cold-related sneezing and nasal secretions are driven partly by cholinergic nerve pathways, not just histamine. First-generation antihistamines block both histamine receptors and muscarinic (acetylcholine) receptors, and they cross into the brain. Second-generation drugs are more targeted and stay out of the central nervous system. That precision makes them better for allergies but worse for colds. The trade-off is real: first-generation antihistamines cause drowsiness, impair driving, and aren’t great to combine with alcohol. They work for cold symptoms, but the sedation is part of the package, not a side effect you can separate out.
Pain Relievers and Fever Reducers
For sore throat, body aches, headache, and fever, nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen and naproxen are genuinely helpful. A systematic review found strong evidence that NSAIDs reduce fever in both adults and children, and most studies showed significant relief for sore throat specifically.11PubMed Central. Nonsteroidal anti-inflammatory drugs in acute viral respiratory tract infections: An updated systematic review Acetaminophen (paracetamol) is another solid option for fever and pain, though it lacks the anti-inflammatory component.
An interesting finding from meta-analyses of sore throat trials is that a single low dose of a corticosteroid like dexamethasone, given alongside standard pain relief, roughly doubled the chance of complete pain resolution at 24 hours and shortened the overall time to pain relief by about five hours.12BMJ. Corticosteroids for treatment of sore throat: systematic review and meta-analysis of randomised trials This isn’t something you’d pick up at a pharmacy, but it’s an option your doctor might consider for a particularly severe sore throat, especially if you’re having difficulty swallowing.
Cough Medications
Over-the-counter cough medicines have a complicated reputation. Dextromethorphan, the most common cough suppressant in pharmacy-aisle products, has mixed trial results. A Cochrane review found that one study favored it over placebo while a second did not.13Cochrane Database of Systematic Reviews. Oral over-the-counter cough preparations for acute cough in the common cold A more recent narrative review found statistically significant reductions in cough frequency and severity when dextromethorphan was used alone or combined with guaifenesin, a mucus-thinning agent.14PubMed. Guaifenesin and dextromethorphan for management of cough and mucus-related cold symptoms in adults: a narrative literature review The evidence is not overwhelming, but these drugs are generally safe in adults at recommended doses and may take the edge off a disruptive cough.
The story is very different for young children. The FDA issued an advisory against using over-the-counter cough and cold products in children under two, and many pediatricians extend that caution further. A survey found that 75% of physicians agreed with this recommendation, and after the advisory, only 15% of parents of children under two said they would continue using these products.15PubMed Central. Physician and Parent Response to the FDA Advisory About Use of Over the Counter Cough and Cold Medications The concern isn’t just about efficacy; in small children, the margin between a therapeutic dose and a dangerous one is narrow.
Honey for Cough
For children over one year old (never under one, due to the risk of infant botulism), honey has surprisingly good evidence as a cough remedy. A systematic review and meta-analysis found that honey improved combined symptom scores, cough frequency, and cough severity compared with usual care.16PubMed. Effectiveness of honey for symptomatic relief in upper respiratory tract infections: a systematic review and meta-analysis A randomized trial in children found that parents consistently rated honey products higher than placebo for nighttime cough relief and sleep quality.17Pediatrics. Effect of Honey on Nocturnal Cough and Sleep Quality: A Double-blind, Randomized, Placebo-Controlled Study Honey’s coating action on the throat and possible anti-inflammatory properties make it a reasonable first-line option for cough in children and adults alike, with the advantage of having essentially no side effects beyond the calories.
Zinc Lozenges
Zinc has some of the most interesting data in the supplement category. A meta-analysis of seven trials found that zinc lozenges shortened the duration of common cold symptoms by about a third, with zinc acetate lozenges showing roughly a 40% reduction and zinc gluconate about a 28% reduction.18PubMed Central. Zinc lozenges and the common cold: a meta-analysis comparing zinc acetate and zinc gluconate, and the role of zinc dosage An individual-patient-data meta-analysis found that by the fifth day of illness, 70% of people taking zinc acetate lozenges had recovered compared with 27% on placebo.19Open Forum Infectious Diseases. Zinc Acetate Lozenges May Improve the Recovery Rate of Common Cold Patients: An Individual Patient Data Meta-Analysis
The catch is timing: zinc lozenges need to be started within 24 hours of symptom onset and taken frequently throughout the day to maintain high concentrations in the throat. Many commercial “zinc cold remedy” products are formulated with added flavoring agents like citric acid that can bind zinc ions and reduce their availability. If you try zinc lozenges, look for simple formulations with zinc acetate or zinc gluconate and minimal additives. Side effects are mild but real, primarily nausea and a metallic taste.
Vitamin C and Vitamin D
Vitamin C is probably the most famous cold remedy, and the evidence is modest but real. A meta-analysis of micronutrient supplements and respiratory infections found that vitamin C supplementation reduced the risk of developing a respiratory infection by a small margin and shortened symptom duration by about 9%.20BMJ Nutrition, Prevention & Health. Effect of micronutrient supplements on influenza and other respiratory tract infections among adults: a systematic review and meta-analysis A meta-analysis focused on children found that vitamin C shortened upper respiratory infection duration by about 1.6 days, though it didn’t significantly reduce the chance of getting sick in the first place.21PubMed. Efficacy of vitamin C for the prevention and treatment of upper respiratory tract infection. A meta-analysis in children
Vitamin D showed a similarly small benefit in that same meta-analysis, reducing the risk of acute respiratory infection and shortening symptoms slightly.22BMJ Nutrition, Prevention & Health. Effect of micronutrient supplements on influenza and other respiratory tract infections among adults: a systematic review and meta-analysis The effects for both vitamins are modest enough that they’re unlikely to turn around a bad cold, but consistent daily supplementation over time may reduce how often you get sick and shave a day or so off each episode.
Antivirals for Influenza and COVID-19
When the infection isn’t just any virus but specifically influenza or SARS-CoV-2, prescription antivirals become relevant. For the flu, oseltamivir (Tamiflu) has been the standard for years. Baloxavir marboxil (Xofluza) is a newer option that works differently and offers the convenience of a single-dose regimen, eliminating adherence concerns. Trials showed it was superior to placebo and comparable to oseltamivir, with the added benefit that it may work against strains resistant to oseltamivir.23PubMed. Baloxavir Marboxil: The First Cap-Dependent Endonuclease Inhibitor for the Treatment of Influenza Both antivirals need to be started within 48 hours of symptom onset to be effective.
For COVID-19, nirmatrelvir-ritonavir (Paxlovid) has become the go-to outpatient treatment for people at risk of severe disease. A study of hospitalized patients found that those who didn’t receive Paxlovid were roughly five times more likely to need hospitalization beyond seven days.24PubMed. Safety and efficacy of Paxlovid in the treatment of adults with mild to moderate COVID-19 during the omicron epidemic: a multicentre study from China Modeling work suggests that Paxlovid can inhibit over 90% of viral replication, but that timing matters: starting treatment three to five days after symptoms appear hits the sweet spot, while starting earlier paradoxically increases the risk of viral rebound without further reducing how infectious you are.25PubMed Central. A retrospective cohort study of Paxlovid efficacy depending on treatment time in hospitalized COVID-19 patients Paxlovid also has significant drug interactions, particularly with statins, certain heart medications, and immunosuppressants, so your pharmacist or prescriber needs to review your full medication list.
Saline Nasal Irrigation
Rinsing your nasal passages with salt water using a neti pot or squeeze bottle is a low-tech approach with some supporting evidence. A Cochrane review found that in children, saline irrigation modestly reduced nasal secretion scores and nasal obstruction compared with no treatment, and the children using saline also needed less decongestant medication.26PubMed Central. Saline nasal irrigation for acute upper respiratory tract infections The effects were statistically significant but small on a clinical scale, so this isn’t a dramatic intervention. It’s safe, cheap, and has no drug interactions, which makes it a sensible add-on for anyone who finds it comfortable. The main precaution is to always use distilled or previously boiled water, never tap water, to avoid the rare but serious risk of amoebic infection.
Herbal Remedies With Clinical Trial Evidence
A few herbal products have been studied in proper randomized trials, though the evidence base is thinner than for conventional drugs. Elderberry (Sambucus nigra) supplementation was found to substantially reduce upper respiratory symptoms in a meta-analysis of controlled trials, which the authors described as a potential alternative to antibiotic misuse for viral infections.27PubMed. Black elderberry (Sambucus nigra) supplementation effectively treats upper respiratory symptoms: A meta-analysis of randomized, controlled clinical trials The included trials were small, so the large effect size should be interpreted cautiously.
Pelargonium sidoides, a South African geranium root extract sold under brand names like Umcka, has been tested in both children and adults. A placebo-controlled trial in children found that symptom scores dropped significantly faster in the treatment group, with cough frequency improving within three days.28PubMed. Effectiveness of Pelargonium sidoides in pediatric patients diagnosed with uncomplicated upper respiratory tract infection: a single-blind, randomized, placebo-controlled study In a separate adult trial, 55% of patients rated the extract as producing at least “major improvement” compared with 15% on placebo by day five.29PubMed Central. Treatment with EPs 7630, a Pelargonium Sidoides Root Extract, Is Effective and Safe in Patients with the Common Cold: Results From a Randomized, Double Blind, Placebo-Controlled Clinical Trial These are encouraging results, but the trials are few and generally small, so herbal remedies belong in the “plausible but not proven” category.
Probiotics and Respiratory Infections
The idea that gut bacteria can affect respiratory immunity sounds implausible, but a systematic review of randomized trials found that probiotic treatment significantly shortened the average duration of respiratory illness episodes and reduced days absent from school or work compared with placebo.30PubMed Central. Effectiveness of probiotics on the duration of illness in healthy children and adults who develop common acute respiratory infectious conditions: a systematic review and meta-analysis A more recent trial in healthy adults found that those taking a probiotic had shorter symptom duration and lower rates of muscle pain during cold episodes, along with measurable changes in inflammatory markers.31PubMed Central. Clinical Efficacy of Probiotics for Relieving Cold Symptoms in Healthy Individuals: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial Probiotics aren’t going to replace a decongestant when you’re miserable at 2 a.m., but daily use over cold season may reduce how long each illness drags on.
The Acetaminophen Double-Dipping Problem
Multi-symptom cold products often contain acetaminophen alongside a decongestant, an antihistamine, or a cough suppressant. This creates a genuine safety hazard because people frequently take a dedicated pain reliever on top of the combination product without realizing both contain acetaminophen. In one study, about 24% of participants demonstrated they would exceed the safe daily dose of four grams using a single acetaminophen product, and nearly 46% would overdose by taking two acetaminophen-containing products simultaneously.32PubMed Central. Risk of unintentional overdose with non-prescription acetaminophen products Acetaminophen overdose is a leading cause of acute liver failure. Before taking any combination cold product, read the active ingredients panel and make sure you’re not doubling up.
Medication Safety During Pregnancy
Pregnant women get colds too, and the question of which medications are safe comes up constantly. A review of the available evidence on common cold remedies during pregnancy found no increased risk with short-term use of standard ingredients like acetaminophen and certain antihistamines.33PubMed Central. Treating the common cold during pregnancy That said, NSAIDs are generally avoided in the third trimester due to effects on fetal circulation, and decongestants (especially oral pseudoephedrine) are approached with caution during the first trimester. Honey, saline irrigation, and acetaminophen are the safest go-to options. Any prescription antiviral, whether for flu or COVID-19, warrants a specific conversation with your prescriber about the risk-benefit balance during pregnancy.