What are common inactive ingredients in veterinary ivermectin pour-on formulations?

1. What “inactive” usually means in pour‑on ivermectin products

Manufacturers label components other than the active drug as “inactive” or excipients; in pour‑on topical solutions these typically serve as carriers (solvents), skin/coat conditioners (emollients), wetting agents (surfactants) and preservatives — functions reflected in ingredient lists for related topical ivermectin products such as lotion and cream where castor oil, cyclomethicone, glycerin, oleyl alcohol, polysorbate 80 and parabens appear ^{[1] [2] [3]}.

2. Concrete examples from available labels and inserts

The drugs.com ivermectin lotion insert lists inactive ingredients including butylated hydroxyanisole, castor oil, cetyl alcohol, cyclomethicone, glycerin, lanolin alcohols, methylparaben, propylene glycol, propylparaben, purified water and shea butter — all common excipients used to solubilize and stabilize topical formulations ^[1]. DailyMed entries for ivermectin cream and tablets likewise list benzyl alcohol, carbomer, di‑isopropyl adipate, polysorbate 80, methylparaben and common tablet excipients such as microcrystalline cellulose and magnesium stearate ^{[2] [7] [8]}.

3. What the pour‑on cattle product documents say (and don’t say)

Cattle pour‑on product monographs and SDSs in the available results focus on dose, spectrum of parasite control and environmental warnings (ivermectin binds to soil and may affect aquatic life) rather than full, standardized excipient lists across brands ^{[5] [9] [4]}. Some country product PDFs are listed (e.g., Health Canada product or distributor labels), but the search results do not consistently display a single universal list of inactive ingredients for all veterinary pour‑ons ^{[10] [11]}.

4. Why human and veterinary topical ingredient lists can differ

Human topical products (lotion, cream) are often formulated for skin tolerability in people and therefore show emollients, humectants and preservatives familiar to dermatology labels ^{[1] [2]}. Veterinary pour‑ons for cattle prioritize rapid spread along the hair/skin, rainfastness and dosing volume; that leads manufacturers to choose solvents and carriers tailored to bovine hide and application equipment — but specific excipients vary by brand and region, and the available product docs emphasize usage and safety rather than a universal excipient roster ^{[5] [4]}.

5. Safety and misuse context highlighted by sources

WebMD and product monographs explicitly warn that veterinary ivermectin formulations are not intended for human use and may contain inactive ingredients unsuitable or unsafe for people; veterinary doses intended for large animals also pose overdose risk if consumed by humans ^[6]. The cattle pour‑on labels also give environmental cautions: ivermectin tightly binds soil and can affect aquatic organisms, underscoring that “inactive” does not mean environmentally inert ^{[4] [5]}.

6. Practical takeaway and how to find precise lists

If you need the exact inactive ingredients for a specific veterinary pour‑on product, check that product’s official label, DailyMed/Health Canada product monograph or the manufacturer’s SDS — those documents list brand‑specific excipients when provided ^{[5] [9] [10]}. The sources in this search provide representative excipients from topical ivermectin lotion and cream (castor oil, cyclomethicone, glycerin, parabens, oleyl alcohol, polysorbate 80, etc.), but available reporting does not present a single, definitive excipient list that applies to all veterinary pour‑on formulations ^{[1] [2] [3] [5]}.

Limitations: the search results include detailed ingredient lists for human topical and oral ivermectin products and some cattle pour‑on monographs, but they do not consistently publish a universal ingredient list for every veterinary pour‑on brand; therefore, brand‑specific product labels remain the authoritative source for an exact inactive ingredient roster ^{[1] [2] [5]}.