The ingredient in Zylkene calming supplement is called alpha-casozepine and is derived from a milk protein called casein.
Zylkene Capsules – full list of ingredients: 
Zylkene for Cats and Dogs Up to 10kg (75mg) composition: Powder 77.3%: Maltodextrin, Casein (Trypsin hydrolysed bovine casein), Magnesium stearate.
Capsule 22.7%: Bovine skin gelatine
Zylkene for Dogs 10-30kg (225mg) composition: Powder 76.9%: Casein (Trypsin hydrolysed bovine casein), Maltodextrin, Magnesium stearate.
Capsule 23.1%: Bovine skin gelatine
Zylkene for Dogs 30-60kg (450mg) composition: Powder: 82.9%: Casein (Trypsin hydrolysed bovine casein), Magnesium stearate.
Capsule 17.1%: Bovine skin gelatine

Zylkene calming supplement contains a natural ingredient derived from a protein in milk called casein that has clinically proven calming effects and helps to comfort cats and dogs. This peptide (protein) molecule supports your pet by sending ‘calming messages’ to the brain via the body’s natural ‘messenger’ system. 

Zylkene is suitable for both long and short term use. For long term use, we recommend you give Zylkene to your pet every day for a month then reassess his/her behaviour and continue if needed. Speak to your vet if it is a long-term concern to ensure there are no underlying issues. For short term use, we recommend giving Zylkene to your pet 1-2 days before the predicted challenging event or when a change in their environment is expected to happen. 

Zylkene calming supplements can be used to help with separation anxiety. We would also recommend that you contact your vet or a qualified behaviourist who will be able to advise more on how to help your dog / cat with separation anxiety. 

We recommend giving Zylkene 1-2 days before the predicted challenging event or when a change in their environment is expected to happen. 

No, Zylkene is not a sedative. Zylkene is a calming supplement that contains a natural milk protein that has clinically proven calming effects to help comfort cats and dogs, and will not make your pet feel drowsy. 

Zylkene is not a medication. Zylkene is a calming supplement that contains a natural milk protein called casein that has clinically proven calming effects to help comfort cats and dogs. Casein is well known to promote the relaxation of new-borns after breastfeeding. 

Zylkene is easy to give, simply sprinkle the powder onto your pet’s food. 

If you are considering using Zylkene for your kitten/puppy we would recommend that you contact your vet who will be best placed to advise on how to use the product. 

Zylkene is suitable for both long- and short- term use. For long term use, we recommend you give Zylkene to your pet every day for a month then reassess his/her behaviour and continue if needed. We recommend speaking to your vet if there is a long term concern to ensure there are no underlying issues, which may need to be addressed alongside behaviour modification therapy. 

If you are considering using Zylkene for your lactating pet, we would recommend that you contact your vet who will be best placed to advise on how to use the product. 

If you are considering using Zylkene for your pregnant pet, we would recommend that you contact your vet who will be best placed to advise on how to use the product. 

Zylkene can be used alongside pheromones. Zylkene is an oral supplement that will help comfort cats or dogs wherever they go inside and outside the home. 

Aggression can be a sign of stress in an animal however Zylkene is not recommended in aggressive animals, and we would therefore not advise its use. Our best advice would be to speak to your veterinary practice and a qualified clinical animal behaviourist regarding your pet. 

Both Zylkene Chews and Zylkene capsules have the same natural ingredient and calms your pet in the same way. The main difference between the two is how you can give it to your pet; Zylkene capsules can be sprinkled onto your pet’s food whereas Zylkene Chews are given like a treat.