A hit Chinese drama put a folk remedy on screen: a hospital department head grinds metronidazole into powder and sniffs it for his rhinitis, on an accountant's advice, while the character Liu Zhengliang — newly back at the small Northeast hospital — watches in shock. A Modern Express report carried by Tencent News on October 29, 2026 collected the scene and the response to it [1]. By the morning of November 2 the story had reached No. 17 on Zhihu's hot list.
The verdict arrives before the safety question opens. US and UK drug references give metronidazole no rhinitis indication and no nasal or inhaled dosage form, so the on-screen remedy fails twice on paper before it fails in a nostril. What public guidance does describe for rhinitis is a pharmacy-level routine of antihistamines, steroid sprays and saline rinses [4] [5] — none of it powdered, sniffed or prescribed by an accountant.
The label excludes the remedy twice over
Metronidazole belongs to the nitroimidazole antimicrobials and works by stopping the growth of bacteria [2]. MedlinePlus, the US National Library of Medicine's drug reference, limits its stated uses to certain bacterial infections, including sexually transmitted diseases and bacterial vaginosis [2]. NHS's page on the drug adds skin infections, rosacea, mouth infections, pelvic inflammatory disease, infected insect bites, skin ulcers, bed sores and wounds, and the treatment and prevention of bacterial and parasitic infections [3]. Neither list names rhinitis.
The second check is the dosage forms. In the US reference the drug "comes as a tablet, a capsule, and suspension (liquid) to take by mouth" [2]. NHS lists tablets, skin gel, vaginal gel, skin cream, an oral liquid and a suppository, plus an injection usually done in hospital [3]. No form in either list enters the nose. In the UK the drug is prescription-only [3].
Both checks carry dates. MedlinePlus's entry was revised on August 15, 2026 [2]; NHS reviewed its page on December 31, 2025 [3]. A remedy that requires the drug in powder form, inhaled, sits outside both lists.
The trick borrows logic from a different disease
The plot's remedy needs one assumption to hold: that a blocked nose is the kind of infection metronidazole treats. NHS's condition pages file rhinitis somewhere else. Allergic rhinitis, it says, is the nose reacting to something the person is allergic to — pollen, house dust mites, animal dander, mould [4]. Non-allergic rhinitis it describes as irritation inside the nose, with causes that include weather changes, exercise, smoke, perfume and paint fumes, alcohol, spicy food, hormone shifts, other medicines, and decongestant sprays used longer than the packet allows [5]. Neither description names the bacterial or parasitic infections the drug's references cover.
MedlinePlus draws the boundary in general terms that apply here: antibiotics do not work for colds, flu or other viral infections [2]. What this teaches: ask what the condition is before matching it to whatever drug is at hand. A drug's reference page answers that question in writing, and in this case the written answer is no.
What the record shows about harm
The powder route matches nothing in the reference; MedlinePlus instructs patients to take the drug exactly as directed [2]. The effects on record are documented for the drug's labeled use, taken by mouth: common ones include nausea, vomiting, stomach cramps and a metallic taste [2]; the serious list includes numbness, pain or tingling in the hands or feet, seizures, coordination problems and confusion [2]. The entry carries an important warning that metronidazole can cause cancer in laboratory animals [2], and it bars alcoholic drinks and products containing alcohol or propylene glycol while the medication is being taken and for at least three days after the final dose, because the combination can bring on nausea, vomiting, stomach cramps, headache, sweating and flushing [2].
What the crushed-powder route itself changes, the sources reviewed here do not document — neither reference covers nasal use, so the effects above describe the drug as labeled, not the scene's method. Using antibiotics without need carries a documented cost of its own: it increases the risk of a later infection that resists antibiotic treatment [2].
The Modern Express report put a clinician on the record: Li Zhiyong, deputy chief physician of ear, nose and throat head and neck surgery at Wuhan University Zhongnan Hospital, warned that the scene is a plot to watch and not a method to copy [1].
What NHS guidance lists for rhinitis
If the powder is not the answer, NHS's guidance for allergic rhinitis starts at the pharmacy: antihistamines, decongestant nasal sprays or drops, steroid nasal sprays, and salt-water rinses [4]. The cautions attach to the decongestants: not for children under 6, and not for longer than 5 days, since longer use can make a blocked nose worse [4]. For non-allergic rhinitis the shelf is similar, with antihistamines, unblocking sprays and saline rinses, and the same caution that decongestant sprays should not run past a week [5]. When pharmacy options run out, the described next step is a GP, who can prescribe steroid nasal sprays or antihistamines [4], or change a medicine that may be causing the symptoms [5].
This is public guidance for a common condition, not advice for any individual case — a line the drama crosses by letting a prescription drug travel on an accountant's tip. Metronidazole is prescription-only in the UK [3]; the on-screen version arrived with no prescriber at all.
What to keep from a scene like this
As drama the scene works; as pharmacy it fails on paper before it fails in the nose — no indication, no nasal form [2] [3]. The habit worth keeping is the one those pages teach: check whether a drug's own reference covers the condition and the route before a plot — or a colleague — supplies the rest.