Onion Syrup for Cough

Onion syrup is a home remedy for cough, prepared in the kitchen based on onions. It is used for cough, usually during a cold.

Origins

Onion for cough is a method passed down through generations in families. We did not find a reliable source describing the history of this tradition in Poland, but survey studies show that it is well known in Central and Western Europe.

In an Austrian study from 2022, parents of 215 children with acute infections who visited a pediatric office filled out a survey. Among home remedies, onion was most frequently mentioned (54 parents, or 25.1% of respondents), and the authors labeled homemade onion syrup as the most traditional folk remedy in this group. In a study from Switzerland and France in 2023, 17 out of 1012 patients in a clinic used onion syrup for cough.

Homemade recipes vary, and we do not describe any of them as a treatment method. If the syrup is sweetened with honey or sugar, the warnings from the “Safety” section apply.

What We Know

Label: Tradition. We did not find any clinical study or review that tested the effectiveness of onion syrup for cough. The authors of the Austrian study state directly that there is no experimental evidence for the benefits of mixtures containing onion.

What Studies Say

• Austria, 2022 (BMC Pediatrics), survey study: 215 children aged 1 to 14 years with acute infections. Onion was the most frequently mentioned home remedy (54 parents, or 25.1% of respondents). The authors note that there is a lack of randomized studies regarding these remedies and no experimental evidence for the benefits of mixtures with onion or ginger.
• Switzerland and France, 2023 (Family Practice), survey study: 1012 patients in primary care. Onion syrup for cough was used by 17 people (1.7%), and 13 of them considered it effective. However, this is patient opinion, not a measurement of efficacy. The authors state that future studies should determine whether such remedies can be safely recommended.
• Spain, 2009 (Allergologia et Immunopathologia), review article: A pediatrician from a university hospital in Madrid discusses “onion for cough” among popular myths and unproven beliefs related to asthma.
• NHS (British public health service): Among home remedies for cough, it lists rest, drinking plenty of fluids, and warm drinks with lemon and honey. Onion syrup is not on this list. The NHS adds that even for lemon with honey and herbal preparations, the evidence is limited.

Safety

Risks

• Botulism in infants from honey. The NHS lists symptoms in young children such as weak or altered crying, difficulty eating, lethargy, reduced activity, and a floppy head, neck, arms, or legs. This condition requires immediate medical attention.
• Sugar. According to the NHS, sugar added to foods and drinks, as well as sugars from honey and syrups, are known as free sugars. Excessive amounts contribute to weight gain and tooth decay.
• Delaying a doctor's visit. Homemade syrup cannot replace a medical examination when a cough persists for a long time or when alarming symptoms described below appear.

Who Should Avoid It

• Children under 1 year of age if the syrup contains honey. The NHS explicitly recommends not giving honey to children younger than 12 months.
• People with diabetes should be cautious with sweetened syrup. The NHS advises individuals with type 2 diabetes not to consume too many products high in sugar. It is best to consult a doctor or dietitian to see if such syrup fits into their diet.
• Pregnant women should consult a doctor or pharmacist first. The NHS reminds that not all medications and herbal remedies are safe for everyone, such as during pregnancy.

Drug Interactions

• The sources we accessed do not describe interactions of onion syrup with medications, as no one has tested this syrup in studies. The absence of a description does not mean that interactions do not exist.
• If you are taking medications regularly, ask a pharmacist before you start regularly consuming homemade syrup.

When to See a Doctor

The NHS states that cough usually resolves on its own within 3 to 4 weeks. You should schedule an appointment with your family doctor if:

• the cough lasts longer than 3 weeks,
• you are losing weight without reason,
• you have a weakened immune system, for example due to chemotherapy or diabetes.

Seek urgent medical help if:

• the cough is very severe or rapidly worsens, for example, you cannot stop coughing,
• you feel very unwell,
• you have chest pain,
• the side of your neck is swollen and painful,
• you have difficulty breathing,
• you cough up blood.

If an infant has received honey and is floppy, cries weakly, or has difficulty eating, you should call emergency services immediately.

Sources

Compiled by the editorial team of informacja.com based on sources. Status as of October 24, 2026. This is not medical advice.