Identify the hormone product and purpose
Progesterone products can be prescribed in different contexts, and instructions belong to the actual prescription. The NHS source inspected here concerns oral micronized progesterone marketed as Utrogestan in hormone replacement therapy. Its advice should not be assumed to cover every route or fertility regimen. [1]
Supplement safety is not comprehensively established
NHS guidance notes that supplements are not generally tested for medicine interactions in the same way as licensed drugs. The source does not establish a specific universal magnesium contraindication, but absence of a named interaction is not blanket clearance. Disclose the full product to the prescriber or pharmacist. [1]
Other ingredients may be the important issue
A magnesium sleep or menopause blend can contain herbs as well as the mineral. The NHS source specifically warns that St Johns wort may reduce how well Utrogestan works and lists several interacting medicine classes. Checking only the magnesium amount can miss the more important interaction. [1]
Magnesium still requires its own suitability check
Elemental dose, kidney function and medicines affected by magnesium absorption interactions remain relevant. The inspected sources do not provide a fixed spacing interval that resolves every concern. Follow the hormone prescription and obtain product-specific advice rather than changing timing independently. [2][1]
Bring both labels to the review
Imagine someone prescribed progesterone adds a night-time mineral blend containing an herb. A compatibility question naming only magnesium leaves out part of the exposure. Review the full blend and prescribed regimen before attributing benefit or adverse effects to the mineral alone. [1][2]
| Detail | Reason to check |
|---|---|
| Exact hormone and route | Instructions are product specific |
| Full supplement formula | May include interacting herbs |
| Kidney function and magnesium dose | A separate mineral-safety question |
| A generic spacing rule | Does not establish compatibility |
Sources for this article
- Taking Utrogestan with other medicines and herbal supplements - NHS
Source consulted: 2026-09-21. This is a reference resource, not a claim that we conducted the studies or tested a product. - Magnesium - Health Professional Fact Sheet
Source consulted: 2026-09-21. This is a reference resource, not a claim that we conducted the studies or tested a product.