Does hyssop help with asthma? What the research shows

The evidence doesn't support hyssop as a treatment for asthma. One human trial exists: a concentrated extract syrup added to standard asthma treatment in 60 adults already diagnosed with asthma, over 4 weeks — and its result went in opposite directions depending on which type of cough a participant had going in.

What the evidence doesn't support

It doesn't support using hyssop, in tea, capsule or any other form, in place of an inhaler or prescribed asthma medication — the one trial that exists added hyssop syrup to standard treatment rather than testing it instead of one. It doesn't support hyssop for asthma broadly, without qualifying which type of cough a person has, since the trial's own result went opposite directions by cough type. And it doesn't support hyssop tea or capsules for asthma specifically — only a concentrated syrup extract was tested, at a dose well above what tea or a typical capsule delivers.

What the trials found

A 2024 randomized, triple-blind, placebo-controlled trial gave 60 adults with mild-to-moderate, physician-diagnosed asthma either a hyssop syrup (6 g of Hyssopus officinalis extract per dose, twice daily — 12 g/day) or a plain sugar syrup, for 4 weeks, added to their routine asthma treatment. The result split by cough type: in participants with a productive cough, the hyssop group showed improvement in lung-function measures (FEV1, peak expiratory flow, MEF25–75%), an asthma control score, and wheezing severity, compared with placebo. In participants with a dry cough, those same measures got worse on hyssop, and five participants — all with dry cough — dropped out because their cough and shortness of breath worsened. Reported side effects in the hyssop group included thirst, dry mouth and throat irritation. This is the only published human trial of hyssop for asthma, or for any outcome, in any form — a single trial, in a specific diagnosed population, with a result that depended heavily on symptom type.

A 2014 study induced chronic asthma-like inflammation in mice using ovalbumin sensitization, then treated one group with Hyssopus officinalis. That group's airway-inflammation markers — eosinophils, IgE and IgG in blood and lung fluid — looked similar to healthy, non-asthmatic mice, compared with worse markers in the untreated asthmatic group. That's a mouse model of induced inflammation, not a study of asthma treatment in people, and it predates the 2024 human trial by a decade without a larger human study following up on it.

Questions people ask

Is hyssop good for asthma?

The only evidence is the one 2024 trial above, and its answer depends on cough type: better measures in participants with a productive cough, worse measures in participants with a dry cough. That's not a general "good for asthma" result, and it's a single, unreplicated trial.

Does hyssop help asthma-related cough?

It depends on the type of cough, according to the one trial that tested it — productive cough improved, dry cough worsened, with five participants discontinuing due to worsening symptoms. That's a reason for caution, not a general recommendation either way.

Is it safe to add hyssop to asthma treatment?

The one trial added hyssop syrup to standard asthma treatment, rather than testing it alone, and even then some participants' symptoms got worse. Anyone with diagnosed asthma should keep taking prescribed treatment and talk to a doctor before adding hyssop or any supplement alongside it.

When to talk to a doctor

Diagnosed asthma that isn't controlled with current treatment is worth discussing with a doctor. Hyssop is not a treatment for asthma, and the one trial that tested it made symptoms worse for some participants — it does not support stopping, reducing or replacing an inhaler or other prescribed asthma medication with hyssop in any form.

Related reading: hyssop benefits: what the research does and doesn't show, hyssop: what the research does and doesn't show, and hyssop side effects.