Valentine's Day: My cat Romeo takes 'Viagra'

Warning: Always consult your veterinarian before giving your pet any kind of medicine

Romeo, my almost 16-year-old cat, has always lived up to his name.

Affectionate, attention-seeking and a natural heart-throb.

But last year we noticed he was becoming breathless after certain activities (stop it!).

After various scans and tests his vet reached for a surprising prescription - a drug normally used for human erectile dysfunction.

We were told he has pulmonary fibrosis and pulmonary hypertension - this is where high blood pressure in the arteries of a cat's lungs, forces the heart to work harder.

Sildenafil citrate – more commonly known by brand name Viagra – was first synthesised in 1989 by chemists working on a treatment for angina and high blood pressure at Pfizer's research laboratory in Sandwich, Kent.

Ten years later the little blue pill hit the shelves in the USA and UK as the first approved oral treatment for erectile dysfunction. It quickly became the fastest selling drug in history with annual sales peaking in 2008 of almost $2bn.

But mention it and people snigger, nudge each other, or reach for tired innuendos.

Its use in veterinary medicine is less well known, but increasingly common.

Generic sildenafil citrate, which Romeo takes in beef flavour, helps to relax blood vessels and improve oxygen delivery.

Dr. Reinero, a specialist at the University of Missouri's BREATHE Clinic (a respiratory and aerodigestive clinic for dogs and cats) said: "There is minimal data around this medication's use for pulmonary hypertension in cats, as it is used off label when other options might be limited."

Dr. Reinero added: "Using sildenafil citrate inappropriately could be dangerous, but appropriately it can can improve quality of life."

And for Romeo it has helped.

But sildenafil citrate can cause side effects such as vomiting, it is known to interact with a range of other drugs and should not be used at the same time as any other drugs that lower blood pressure.

Romeo doesn’t know his medication's name, its history, or the jokes it still unfairly provokes - it is just one of the reasons his world feels a little bigger again this Valentine's Day.

You can follow BBC Hampshire & Isle of Wight on Facebook, X (Twitter), or Instagram.