London: Combining four blood pressure drugs into a single pill could be twice as effective as existing treatments, researchers have found.
The results of the small pilot trial, published in the Lancet medical journal, could offer a new approach for the hundreds of thousands in the UK who take daily tablets for their blood pressure.
In a breakthrough trial, every patient given the four-in-one 'quadpill' saw their blood pressure drop to healthy levels within a month.
And because each drug is included in much lower doses than in conventional tablets, experts believe the combined medication will minimise side-effects.
High blood pressure - or hypertension - affects more than 17 million Britons, or one adult in three.
The condition vastly increases the risk of heart attacks, strokes and vascular dementia but, because it has no symptoms often until it is too late, only half of people even know they are at risk.
Of those who have been diagnosed, hundreds of thousands take daily pills to control their blood pressure. But they normally take just one drug - and only about half of patients see their blood pressure fall to a healthy level.
The new study saw a 100 per cent success rate. However, the researchers from the George Institute at Sydney University stressed that only 18 patients took part in the trial. Further research is needed to see if the results can be repeated, they said, but these initial findings are very exciting.
Study author Professor Clara Chow said: 'Most people receive one medicine at a normal dose but that only controls blood pressure about half the time. In this small trial blood pressure control was achieved for everyone. Trials will now test whether this can be repeated and maintained long-term.'
The study involved giving patients a single capsule containing a quarter-dose of each of four common blood pressure drugs - irbesartan, amlodipine, hydrochlorothiazide and atenolol.
Researchers believe reducing the dose of each drug minimises the risk of side-effects, which can include swollen ankles and kidney abnormalities.
Even though the dose of each drug was lower, combining them increased their impact.
Professor Chow said: 'Minimising side-effects is important for long-term treatments - we didn't see any issues in this trial, as you would hope with very low-dose therapy, but this is the area where more long-term research is most needed.
'This could be an incredibly important step in helping to reduce the burden of disease globally.' Professor Metin Avkiran, associate medical director at the British Heart Foundation, said: 'High blood pressure is a major risk factor for strokes and heart attacks.
'Although the findings are encouraging and may lead to effective treatments without side effects... more research is needed to confirm the safety of the quadpill, its long-term effect on blood pressure and ultimately whether it reduces a person's risk of having a stroke or heart attack, before it should be considered in clinic.
'Since the majority of people with high blood pressure have no symptoms, a big part of the battle is identifying who has it. If you are concerned, we recommend speaking to your GP.'