If an animal has eaten this plant, the ASPCA Animal Poison Control Center is (888) 426-4435, as printed on the record this page reproduces. A consultation fee may apply.
This page quotes a published document. Everything below in quotation marks is copied word for word from ASPCA Animal Poison Control Center: Field Horsetail, published by ASPCA APCC and retrieved on 2026-09-16. The quotations are excerpts; the document itself is linked and is the authority. Nothing has been reworded.
According to the ASPCA Animal Poison Control Center record, Field Horsetail (Equisetum arvense, family Equisetaceae) is toxic to horses. Toxic principles: Thiaminase. Clinical signs listed: Thiamine deficiency: weakness, weight loss, staggers, tremors, death. The record was retrieved on 2026-09-16 and is linked below.
The record
- Scientific name
- Equisetum arvense
- Family
- Equisetaceae
- Additional common names
- Scouring rush, Common horsetail, Western horsetail
- Toxicity
- Toxic to Horses
- Toxic principles
- Thiaminase
- Clinical signs
- Thiamine deficiency: weakness, weight loss, staggers, tremors, death
Where this comes from
This is the ASPCA Animal Poison Control Center record for Field Horsetail, at https://www.aspca.org/pet-care/aspca-poison-control/toxic-and-non-toxic-plants/field-horsetail, retrieved on 2026-09-16. The fields above are the record’s own, shown without change. The ASPCA keeps the record current; the page here is a copy from that date.
This page is information, not a prescription. The right dose for an animal depends on its weight, its age, what else it is taking and what is wrong with it. Those are judgements only the veterinarian who has examined your animal can make. Ring your practice before giving anything.
Sources
- ASPCA Animal Poison Control Center: Field HorsetailASPCA APCC · retrieved 2026-09-16
“Thiamine deficiency: weakness, weight loss, staggers, tremors, death” (Clinical Signs)
Related
From Glarda
A lifetime record of your animal's care that belongs to you, not to one clinic. Printable, and readable by any vet you take them to.