A stressed animal doesn't respond to being told to calm down, which is why plug-in diffusers work on the room rather than the pet directly. Beaphar's StressLess diffuser uses natural herbal oils released into the air rather than anything given by mouth.

It's a starter kit with one plug-in unit and one 30ml refill, using Valerian and Lavandin oils, and Beaphar say it's effective across an area of up to 50 square metres. The calming effect is said to begin around one hour after it's plugged in, and one refill is described as giving up to 4 weeks of use.

• Plug-in diffuser plus one 30ml refill
• Uses natural herbal Valerian and Lavandin oils
• Effective in areas up to 50 square metres
• Calming effect begins around 1 hour after plugging in
• Up to 4 weeks of use per refill
• For cats and dogs of all life stages

On installation. Beaphar are specific about where this can go: only in a standard 230V socket, never on an extension lead, and it needs at least 1.20m of clearance above it — not tucked under furniture or by a draughty window. It's also stated as harmful to aquatic life, so keep it away from fish tanks.

Who it's for: owners of a cat or dog reacting to a specific stressor — fireworks, a new pet, a house move — who want a plug-in aid for the room rather than something given directly to the animal.