Many people use hormone medicines that go on the skin, as gels, creams or sprays, for example to ease menopause symptoms [1]. A 2022 review in Veterinary Record Open describes how these medicines can pass from a person’s skin to a pet [1]. The authors call this secondary exposure, and say it poses a risk to animals as well as people [1].
If your pet has new hair loss or skin and coat changes and someone in your home uses a hormone medicine on their skin, see your vet and mention it.
How pets are exposed
The review explains that pets are usually exposed through contact with the skin where the medicine was put on, often the forearms [1]. The cases it describes involve gels, creams and sprays; the authors found no published reports of secondary exposure from skin patches [1].
The review says young animals are at greatest risk, because they are small, still developing and more likely to be in close contact with adults at home [1].
Hair loss and skin changes
The review states: “Oestrogen‐induced alopecia is well described in dogs” [1]. Alopecia means hair loss. Oestrogen is the hormone in many menopause medicines.
The authors add that this kind of hair loss in dogs has been linked to hormones from outside the body in some cases [1]. In dogs, it is one of the skin and coat changes a vet may look into.
Far less is known about cats. The authors knew of only one earlier documented case in a cat, alongside the cat reports they reviewed [1].
Other signs
The review says the signs reported in animals included long-lasting signs of being in heat, poor growth and birth defects [1]. If you notice any of these, or any change you cannot explain, see your vet.
Why telling your vet matters
The authors say this exposure can be missed, and that vets should consider it when signs have no clear cause [1]. They stress that vets need a detailed history to spot these cases [1]. Tell your vet about any hormone medicine that anyone in your home puts on their skin.
Lowering the risk at home
The review says the risk is low when people follow the product information closely [1]. The steps it mentions include letting the treated skin dry and covering it with clothing [1]. In a case in a child that the review describes, poor hand washing after putting the gel on was thought to be the likely source [1].
If you use a hormone medicine on your skin, ask your own doctor or pharmacist:
- whether you should cover the treated skin;
- when and how to wash your hands after putting it on;
- how to keep your pet from touching or licking the treated area.
Your pet’s care belongs with your vet. Do not try to treat hair loss or skin changes at home without a vet’s advice.
FAQ
Can a hormone cream on my arm affect my dog?
It can. The review describes animals exposed through contact with skin where a hormone medicine was put on [1].
Are cats at risk too?
The review includes reports in cats as well as dogs, but much less has been published about cats [1].
Are other skin medicines for people a risk?
Some are. See our guide to prescription skin creams for people and pets. For hair loss linked to a dog’s own hormones, see sex hormone skin problems in dogs.
The bottom line
Hormone gels, creams and sprays that people put on their skin can reach pets through contact. In dogs, oestrogen is a known cause of hair loss [1]. If someone at home uses one, ask your doctor how to keep the medicine away from your pet, and if your pet has hair loss or skin changes, see your vet and mention the medicine.
This article is for general information only and does not replace advice from your veterinarian. If your pet has new hair loss or skin changes, see your vet.
Sources
- Sjöström K, Mount J, Klocker A-K, Arthurson V. A review of adverse events in animals and children after secondary exposure to transdermal hormone-containing medicinal products. Vet Rec Open. 2022;9:e48. doi:10.1002/vro2.48. https://pmc.ncbi.nlm.nih.gov/articles/PMC9614385/ (CC BY 4.0, https://creativecommons.org/licenses/by/4.0/)