Johnson's Evening Primrose Oil Capsules are a natural dietary supplement rich in essential fatty acids (EFAs) designed to promote healthy skin and coat in both dogs and cats, The EFAs help alleviate dry and irritated skin, scurf, and itching associated with allergies like flea bites. Beneficial during moulting and for pets experiencing heavy hair loss. 
Johnson's Evening Primrose Oil Capsules, are a natural dietary supplement for dogs and cats from 8 or 12 weeks of age onwards, depending on the source. They are rich in essential fatty acids (EFAs), including gamma-linolenic acid
Promotes healthy coat and skin: Helps alleviate dry and irritated skin, scurf (dandruff), and other skin problems.
Aids in managing allergy-based skin conditions: Can be beneficial for issues caused by flea infestation, according to Petwell, and Pet Care By Post.
Supports coat growth: Especially helpful during moulting or heavy hair loss.
May contribute to general well-being.
Natural ingredients. 
Cats and small dogs (under 10kg): 1 capsule per day.
Medium dogs (10-25kg): 2-3 capsules per day.
Large dogs (25-45kg): 3-5 capsules per day.
Very large dogs (over 45kg): 5-6 capsules per day. 
The capsules can be given whole or mixed with food. 
Evening Primrose Oil is generally well tolerated, but high doses may cause diarrhea or other digestive issues, says Annimally. It's always best to start with a small amount and observe your pet's reaction. 
Important: If your animal suffers from epileptic conditions, consult a Veterinary Surgeon before giving Evening Primrose Oil. In high doses, Evening Primrose Oil has a blood-thinning effect, so it should be avoided within 14 days of a surgical or dental procedure or if your pet is on other blood thinners. 
Customers generally report positive results with this supplement, noting improvements in their pets' skin and coat conditions, reduced itching, and increased shine and softness. Some customers specifically praise its effectiveness for addressing skin allergies and problems related to flea infestation. The product is also considered good value for money.