Noradrenaline

Noradrenaline is a messenger substance that regulates blood pressure and heart rate in your dog’s body – and can literally save lives in emergency medicine.

In Switzerland, it is mainly produced in the adrenal glands and the sympathetic nervous system. Interestingly, noradrenaline works on two levels simultaneously – as a neurotransmitter directly in the brain and as a hormone that acts via the bloodstream. In the event of an acute threat – a car brakes sharply, a strange dog charges towards you – noradrenaline is why your dog can react in fractions of a second. No thinking, just reaction.

When does my dog receive noradrenaline from the vet?

Short answer: only in genuine emergencies. Vets resort to noradrenaline exclusively when a dog’s circulation is at risk of collapsing. It is administered via a venous catheter – there simply are no tablets or subcutaneous injections for this.

The situations in which this becomes necessary are invariably serious: An insect sting triggers a severe allergic reaction, and blood pressure drops. After complex surgeries, the cardiovascular system sometimes cannot remain stable on its own. Or after a road traffic accident with significant blood loss – there, noradrenaline bridges the gap until other measures take effect.

If you notice pale mucous membranes, a barely palpable pulse, or realise that your dog is losing consciousness – then every single minute counts. Go to the vet immediately.

How does noradrenaline work in my dog’s body?

The mechanism is direct: noradrenaline constricts blood vessels, blood pressure rises, and the heart pumps more forcefully and faster. The result – the brain, heart and kidneys continue to be supplied with oxygen, even though the body is actually under extreme stress.

In a healthy dog, this happens entirely automatically as soon as it is excited or exerting itself. Anyone who has ever observed their dog panting after an exuberant game of fetch and can practically feel its heart pounding – that is noradrenaline at work. In emergency medicine, this natural reaction is artificially triggered and thus used in a controlled manner.

An important difference to adrenaline: noradrenaline acts more specifically on the vessels and interferes less with the entire nervous system. For the vet, this means significantly more control over the dosage.

What side effects can noradrenaline have?

Blood pressure can rise too sharply, thereby straining organs. It becomes particularly tricky if the vessels in the paws or ears constrict too much – this can permanently impair circulation. Not a theoretical risk, but a genuine reason why monitoring is so intensive.

Arrhythmias can occur if the heart is overstimulated – recognisable by an irregular heartbeat or shortness of breath. For this reason, the vet continuously monitors ECG and blood pressure throughout the entire treatment.

And one more thing that shows how precise the administration must be: if noradrenaline accidentally leaks outside the vein into the tissue, tissue death can occur there. With experienced vets, this practically never happens – but it explains why this procedure takes place exclusively under professional conditions.

Monitoring during noradrenaline treatment

During treatment, your dog is connected to several devices: the ECG shows the rhythm and frequency of the heart, a blood pressure cuff continuously measures the pressure in the arteries. The vet also regularly checks the circulation of the paws and gums – if these become pale or cold, the dose must be adjusted immediately.

Mostly, this all lasts only a few hours until the circulation has stabilised on its own. No long hospital stays if everything goes well.

By the way: in many practices, you are allowed to stay with your dog during treatment. Even under anaesthesia, your presence can measurably reduce stress – do not underestimate this.