Are there risks or side effects of taking ivermectin for coughs or upper respiratory infections?

1. What ivermectin is and how it’s approved — baseline context

Ivermectin is an antiparasitic drug approved for human use against infections such as onchocerciasis and strongyloidiasis; dosing is weight‑based and typically a single oral dose for those indications ^{[6] [1]}. MedlinePlus and FDA commentary cited in government summaries note heightened public attention to ivermectin during the COVID‑19 era and warn people not to take veterinary formulations because those are not evaluated for human safety ^[5].

2. Common, expected side effects — what most people experience

Drug reference sources list common, usually mild side effects including dizziness, headache, somnolence, nausea, diarrhea, fatigue and swelling; manufacturers and drug guides advise reporting adverse events to regulators and consulting a clinician if symptoms are concerning ^{[7] [1] [2]}. Healthline and Drugs.com both emphasize that many adverse effects are transient and can resolve as the body adapts ^{[2] [7]}.

3. Respiratory symptoms and “post‑treatment” reactions — cough can occur

Several sources specifically record cough and other short‑term respiratory complaints after ivermectin, especially when treatment triggers immune responses against parasites. A classic pattern is the Mazzotti‑type reaction — fever, itching, myalgia and cough — that arises as microfilariae are killed and is documented in clinical series and reviews ^{[4] [8]}. In one study of high‑density bancroftian microfilaremia, 97% of treated patients had side reactions and the most common were fever, headache, weakness, myalgia and cough appearing within 12 hours and subsiding within 72 hours ^[4].

4. Serious but rarer harms — neurologic, hepatic, dermatologic, and encephalopathy risks

Pharmacovigilance and case reports identify rare but serious adverse drug reactions: encephalopathy (particularly among patients coinfected with Loa loa), severe skin reactions (toxidermias), and hepatic or renal disorders ^[3]. Systematic safety reviews and clinical case reports document neurological serious adverse events and raise questions about mechanisms; some serious neurologic events have been reported outside onchocerciasis settings as well ^{[3] [9]}.

5. Overdose, self‑medication, and veterinary products — heightened risk

Reports of toxicity often involve supratherapeutic dosing or self‑medication; case studies describe neurologic symptoms (confusion, hallucinations, decreased sensorium) after taking high or repeated doses of ivermectin for presumed viral infections ^[9]. Public health sources explicitly warn against taking animal ivermectin products because formulations and safety in animals are not equivalent to human medicines ^[5].

6. What this means if you have a cough or URTI — practical takeaways

Available sources do not support using ivermectin to treat ordinary coughs or common upper respiratory infections; authoritative drug information frames ivermectin as for specific parasitic diseases and lists respiratory complaints mainly as possible side effects or part of post‑parasite‑kill reactions ^{[1] [5] [4]}. If someone takes ivermectin and develops new or worsening cough, fever, confusion, severe rash, jaundice, or neurologic symptoms, the cited guides advise seeking medical care and reporting adverse events to regulators ^{[1] [2]}.

7. Competing perspectives and limitations in the reporting

Clinical references and pharmacovigilance studies agree on common mild side effects but differ in emphasis: older parasitology literature highlights the predictable Mazzotti‑type reactions (including cough) tied to parasite die‑off ^{[4] [8]}, while modern drug pages stress typical gastrointestinal and neurologic complaints alongside rare serious events and regulatory cautions ^{[1] [2] [3]}. Available sources do not provide randomized‑trial evidence supporting ivermectin for non‑parasitic respiratory infections; they also do not quantify absolute risks of cough when people without parasitic infections take the drug, beyond case reports and adverse‑event registries (not found in current reporting).

8. Bottom line — risk vs. benefit for cough/URTI

Ivermectin carries known side effects, including transient cough as part of immune‑mediated reactions in parasitic disease treatment and rare serious neurologic, hepatic, and dermatologic reactions; because it is not approved for ordinary coughs or typical upper respiratory infections, the potential harms outweigh unproven benefits for those conditions according to the cited drug information and public health summaries ^{[4] [1] [3] [5]}. If someone has taken ivermectin and is symptomatic, seek medical evaluation and follow reporting guidance in the product literature ^{[1] [2]}.