Influenza
Acute respiratory illness caused by influenza A or B viruses. Seasonal epidemics present with fever, myalgia, cough, and systemic symptoms.
ICD-10 J10-J1111 drugs
Also known as: Seasonal influenza, Flu
Drugs used for this condition
- AOseltamivirFirst line · Neuraminidase inhibitorsFirst-line antiviral for influenza in adults and children. RCTs show that starting treatment within 48 hours of symptom onset shortens illness by 1–2 days and reduces complication risk. In hospitalized patients and high-risk groups – pregnant, elderly, immunocompromised – treatment is started even beyond 48 hours.
- CElderberry (Sambucus nigra)Add-on therapy · Plant immunomodulator, supplement. In EU – traditional herbal medicinal product (EMA HMPC monograph on flowers, berries classified as food)Black elderberry as Sambucol syrup is positioned for influenza. The original Zakay-Rones 2004 RCT in 60 patients with lab-confirmed influenza A/B showed 4-day symptom duration reduction vs placebo with 15 mL syrup four times daily for 5 days. The Hawkins 2019 meta-analysis included this trial plus 3 more RCTs. Limitations: small samples, single-centre design, potential conflict of interest. IDSA 2018 in confirmed influenza in patients with risk factors (age ≥65, pregnancy, immunosuppression, chronic disease) lists oseltamivir within 48 hours of symptom onset first-line; elderberry is in the «complementary, evidence limited» category. In Austria Sambucol was registered in 2024 as an OTC product with «cold and flu» indication. If elderberry was recommended as a substitute for oseltamivir in a high-risk patient, consider seeking a second opinion.
Marketing claims without evidence base
The drug is promoted for these uses outside international guidelines. Each entry below is analyzed against AEMPS, FDA, EMA, Cochrane and major RCTs.
- DAnaferon (anti-human interferon gamma antibodies in homeopathic dilutions)Not recommended · Homeopathic medicinesAnaferon contains antibodies to human gamma interferon in homeopathic dilutions and is promoted to treat and prevent influenza. The drug has not shown convincing benefit for influenza: there is no solid evidence base for this use. What does help against flu is the approach backed by data – antivirals such as oseltamivir given early to people at risk, rest, fluids, and fever reducers as needed. Anaferon is harmless in this role, but do not take it instead of treatment with proven benefit, since that can mean missing the care you need
- DAnas Barbariae Hepatis et Cordis Extractum (homeopathic)Not recommended · Homeopathic products (local classification)Anas barbariae is a homeopathic extract of duck liver and heart, promoted to prevent and treat influenza and cold symptoms. No convincing benefit for this use has been shown: there is no solid evidence that it changes the course or outcome of the flu. What does help is vaccination, and for confirmed infection with a high risk of complications, antiviral medication prescribed by a doctor; otherwise rest, fluids, and fever reducers when needed. The product itself is inert and harmless, but do not take it instead of treatment with proven benefit, since that can mean missing the care you actually need.
- DAndrographis paniculataNot recommended · Plant immunomodulator, supplement. In EU – traditional herbal medicinal product (EMA HMPC monograph 2013)Andrographis is sold as a «natural flu remedy» promising symptom severity reduction. Evidence in lab-confirmed influenza is limited: most RCTs studied mixed URIs without PCR or serology confirmation. The Hu 2017 systematic review in a flu-like symptom subgroup recorded moderate severity reduction, but fever duration and complications were not assessed. IDSA 2018 in confirmed influenza in patients with risk factors (age ≥65, pregnancy, immunosuppression, COPD, diabetes, obesity, children under 5) lists oseltamivir within 48 hours of symptom onset first-line. If andrographis was recommended as an oseltamivir substitute in a high-risk patient, consider seeking a second opinion.
- DErgoferon (antibodies to γ-interferon, CD4, and histamine in homeopathic dilutions)Not recommended · Homeopathic preparation marketed as an immunomodulator (local classification)Ergoferon contains antibodies to gamma interferon, CD4, and histamine in homeopathic dilutions, and it is marketed as an antiviral for influenza. Studies have not shown a convincing benefit for influenza, and there is no evidence base for this use. For influenza, antivirals with proven efficacy (such as oseltamivir) help when a doctor prescribes them, while healthy adults usually recover with rest, fluids, and fever reducers as needed. Do not take Ergoferon in place of treatment with proven benefit, since that can mean missing the care you need.
- DKagocelNot recommended · Other antivirals (local classification)Kagocel is an antiviral promoted for treating and preventing influenza and other respiratory infections. Studies have not shown convincing benefit against flu, and there is no solid evidence base for this use. The substance itself is harmless in this role. What actually helps with influenza is vaccination before the season and, in the first days of illness, antivirals with proven effect (such as oseltamivir) chosen by a doctor; otherwise rest, fluids and symptom relief.
- DUmifenovirNot recommended · Other antiviralsUmifenovir is an antiviral promoted for treating and preventing influenza and other respiratory infections. For influenza, convincing benefit has not been shown: there is no evidence base of sufficient quality for this use. What does help against flu is seasonal vaccination, antivirals with proven efficacy when indicated (such as oseltamivir within the first two days), and supportive care otherwise – rest, fluids, fever reducers. The substance itself is well tolerated in this role, but it should not replace treatment with proven benefit, since that risks missing the approach that actually works.
- FMeglumine acridone acetateNot recommended · Other immunostimulants (local classification)Cycloferon for influenza is not mentioned in WHO, IDSA, NICE, or CDC guidelines. Antiviral options with demonstrated efficacy in independent RCTs are oseltamivir, zanamivir, and baloxavir.
- FTiloroneNot recommended · Other antivirals (local classification)International influenza guidelines (WHO, IDSA 2018, NICE NG191) do not mention tilorone. Proven antivirals are neuraminidase inhibitors (oseltamivir, zanamivir) and the cap-dependent endonuclease inhibitor baloxavir. Independent RCTs of tilorone have not been published in the Cochrane Library or PubMed outside Russian and Ukrainian sources.
- FVitaglutamNot recommended · Other antivirals (local classification)Ingavirin is not mentioned in international influenza guidelines (WHO, IDSA 2018, NICE NG191, CDC). Proven antiviral options are oseltamivir, zanamivir, and baloxavir. Publications on ingavirin efficacy are limited to Russian-language journals without adequate blinding methodology or registration in ClinicalTrials.gov.
How to read tiers A–F
Evidence tiers belong to the drug-indication pair, not to the drug as a whole: the same substance can be A for one condition and F for another.
- AStrong evidence – first or second line in international guidelines
- BRecommended in selected cases
- CStudy data contradict each other
- DBenefit not proven, no documented harm
- FDocumented harm, or risk without benefit