Open Source Apothecary At Home / Breathing and airways

Coughs and colds: honey, zinc, and the honest list

Honey beats most cough medicines in trials and is the only thing on this page a child can be given safely. Above one year.

remedy

The common cold is a viral illness with no cure, and the honest list of what shortens or eases it is short and modest.

Honey for cough. This is the strongest single recommendation here. Randomised trials find honey reduces cough frequency and severity in children better than placebo and at least as well as dextromethorphan. It is safe above one year of age, cheap, and it works. It must not be given to a baby under 12 months because of infant botulism.

Zinc. Trials of zinc lozenges or syrup taken within 24 hours of onset show a reduction in cold duration of roughly a day to a day and a half, with the usual caveats: heterogeneity, and a nasty taste and nausea that cause people to stop. Zinc acetate and zinc gluconate lozenges are the studied forms. Zinc nasal gels have caused permanent anosmia (loss of smell) and should not be used.

Vitamin C. Regular supplementation does not prevent colds in the general population. It may slightly shorten duration. Taken only at onset it does essentially nothing. The one well-established use is in people under extreme physical stress — marathon runners, soldiers in the cold — where it halves the incidence.

Echinacea. Trials are heterogeneous and the pooled result is small and inconsistent. It is generally safe.

Pelargonium sidoides has trials showing reduced duration and severity in acute bronchitis, and it is licensed for that in some countries. Reasonable for a productive bronchitis cough.

Elderberry has small trials showing reduced duration of influenza symptoms. The trials are small and some have been criticised for their analysis; it is generally safe but has been associated with GI upset.

Andrographis has small trials showing reduced symptom severity in upper respiratory infection, sometimes in combination.

Thyme and ivy are the traditional cough preparations; thyme has small trials as a cough syrup component and both are used in licensed products in Europe. A thyme infusion with honey is a reasonable household remedy.

Saline nasal irrigation is the under-rated intervention here. It reduces symptoms and medication use in rhinitis and sinusitis and it is nearly free.

What does not work. Antibiotics for a cold. Vitamin C at onset. Most cough syrups, which in trials perform no better than placebo — except that a demulcent and honey do, so the "cough syrup" that works is the one that is basically honey and a demulcent.

What the studies found

Preparation

Honey for cough (over 1 year of age only)

• 1-2 teaspoons (or 0.5-1 teaspoon for a child aged 1-5), as needed, up to a few times daily
• Given alone or stirred into a warm (not boiling) drink
• No honey under 12 months. Ever. Infant botulism.

Thyme and honey cough syrup

• 2 g dried thyme per 250 mL water, infused covered for 10 minutes, strained
• Add an equal volume of honey and stir to dissolve
• Take 1-2 teaspoons as needed
• Keeps about 2 weeks refrigerated

Zinc lozenges

• Zinc acetate or gluconate lozenges, about 75 mg of elemental zinc daily in divided doses, started within 24 hours of onset
• Take with food to reduce nausea; the taste is unpleasant
• Do not use zinc nasal gel or spray — it has caused permanent loss of smell.

Saline nasal irrigation

• 1/2 teaspoon of non-iodised salt and a pinch of bicarbonate in 250 mL of previously boiled, cooled water
• Irrigate each nostril once or twice daily
• Use only boiled-and-cooled, distilled or sterile water. Tap water has caused fatal amoebic infection.

Sage and salt gargle for a sore throat

• 1-2 g dried sage infused in 250 mL water, strained, plus 1/4 teaspoon of salt
• Gargle, do not swallow
• Sage has small trials for sore throat; the salt gargle is soothing

Pelargonium

• Standardised extract per label, for acute bronchitis
• Not for children under 1

Elderberry

• Standardised syrup or extract per label; small trials, influenza symptoms

Vitamin C

• No benefit for cold prevention at ordinary doses; the stress-population finding does not generalise
• At onset it does essentially nothing

Cautions and interactions

• No honey under 12 months of age. Infant botulism.
• Do not use zinc nasal gel or spray. Permanent anosmia has occurred.
• Never use unboiled tap water for nasal irrigation. Use boiled-and-cooled, distilled, or sterile saline.
• Do not use eucalyptus, camphor or menthol rubs on or near the face of an infant or young child.
• Echinacea is in the daisy/ragweed family — avoid with a known allergy to that family.
• Pelargonium and echinacea can interact with drugs through CYP enzymes.
• Honey is sugar. Substantial daily doses matter in diabetes.

When this is not a self-care problem — get help

• Breathlessness at rest, chest pain, coughing blood, a high fever that persists, confusion, or a stiff neck — medical assessment.
• A baby under 3 months with a fever; a child who is drowsy, floppy, breathing fast or noisily, or not drinking — emergency assessment.
• A cough lasting more than 3 weeks, or with weight loss or night sweats — assessment; this is not a cold.

Known interactions

• Echinacea, pelargonium: possible CYP-mediated interactions.
• Zinc reduces absorption of antibiotics and iron. Separate by 2 hours.

Related

• Influenza and when it is serious
• Hay fever and allergic rhinitis
• Sinusitis: irrigation, time, and when antibiotics are actually needed
• Sore throat
• Children: smaller, and different
• Fever: what it is for, and when it means something else

Sources

1. Effect of peri-intubation non-pharmacological interventions on postoperative laryngeal symptoms: A systematic review with meta-analysis and meta-regression. Intensive & critical care nursing 2024; doi:10.1016/j.iccn.2024.103728 PubMed 38861781
2. Vitamin C reduces the severity of common colds: a meta-analysis. BMC public health 2023; doi:10.1038/s41430-022-01091-9 PubMed 38082300
3. Interventions for preventing influenza: An overview of Cochrane systematic reviews and a Bayesian network meta-analysis. Journal of integrative medicine 2021; doi:10.1016/j.joim.2021.09.001 PubMed 34544670
4. Effectiveness of honey for symptomatic relief in upper respiratory tract infections: a systematic review and meta-analysis. BMJ evidence-based medicine 2021; doi:10.1136/bmjebm-2020-111336 PubMed 32817011
5. Safety of Andrographis paniculata: A systematic review and meta-analysis. Pharmacoepidemiology and drug safety 2021; doi:10.1002/pds.5190 PubMed 33372366
6. Vitamin C as a Supplementary Therapy in Relieving Symptoms of the Common Cold: A Meta-Analysis of 10 Randomized Controlled Trials. BioMed research international 2020; doi:10.1002/14651858.CD000181.pub3 PubMed 33102597