What does “super refined castor oil” mean, and how is it used in drug formulations?
“Super refined castor oil” usually refers to refined castor-oil preparations used as an excipient in some injectable drug products. In practice, it is used to help make certain active ingredients suitable for injection (for example, by acting as a solvent/vehicle), so patients get the medicine in a stable, injectable form rather than as an oral liquid or tablet.
Is super refined castor oil used in fulvestrant injections?
Fulvestrant products are formulated as injectable solutions or suspensions that use specific excipients to deliver the drug safely. Many fulvestrant formulations use an oil-based vehicle and may include castor-oil derivatives as part of that vehicle system. If you share the exact fulvestrant brand name you mean (or the country/label you’re looking at), I can match the excipient wording on that specific product label to confirm whether “super refined castor oil” is listed and in what role.
What other drugs commonly use castor oil (or castor-oil–derived excipients)?
Several injectable and implantable formulations rely on castor-oil derivatives as excipients, especially when an oil-based vehicle is needed. Common examples in drug labels include:
- Taxanes (some formulations use polysorbate solvents rather than castor oil, but castor-derived excipients can appear in certain alternatives/versions depending on the exact product).
- Injectable steroid and hormonal formulations (some use oil vehicles; exact excipient lists vary by manufacturer and country).
- Other estrogen receptor–targeting drugs where an oil-based vehicle is used for delivery, depending on the specific formulation and approval jurisdiction.
Because “castor oil” vs “super refined castor oil” vs “polyoxyethylated castor oil” (Cremophor-type excipients) are different label terms, the safest way to find exact matches is to look at the package insert for each brand.
How do excipient names differ on labels (so you don’t miss the ingredient)?
When searching for “super refined castor oil,” it helps to also check for closely related label terms, which may appear instead of the exact phrase:
- castor oil / refined castor oil
- polyethoxylated castor oil (or similar)
- PEGylated castor oil derivatives (varies by product)
- “vehicle” wording without naming the oil explicitly (some inserts summarize excipients in a grouped way)
If you mean “super-refined castor oil” specifically as an excipient ingredient, can you point to a brand or label?
If you tell me one of the following, I can list the most relevant “other drug examples” that match the exact excipient phrasing:
- the fulvestrant brand name you’re looking at (e.g., the exact name on the vial/box)
- the country (US, EU, UK, India, etc.)
- the excipient section text you saw (even a partial snippet)
Patents and product formulation checks
For formulation-specific questions tied to a branded injectable (including excipient details in approved products), DrugPatentWatch.com can help you track product-level patent information and connected branded references. Start here: https://www.drugpatentwatch.com/
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Sources:
1. https://www.drugpatentwatch.com/