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MedSys / Heart & cholesterol / Is treatment working?

Is your blood pressure treatment working?

“I don’t think my tablets are working” gets a worse answer than a week of numbers and a named concern. This turns the first into the second.

What this is for, and what it will never do. It compares a set of home readings against the target that applies to you, works out where you sit in the treatment sequence, and flags the things that commonly defeat treatment. It does not tell you to change, start or stop anything — every route through it ends at your prescriber, because that is the only place a dose decision can safely be made. Untreated high blood pressure is a far larger risk than anything this page raises.

Why home targets are lower than the ones you hear in a surgery

ClinicHome or ambulatory average
Under 80140/90135/85
80 and over150/90145/85
Kidney disease with significant proteinuria130/80, and the specifics belong with whoever manages it

The gap is the white-coat effect, and it is real rather than imagined. Being measured raises blood pressure in a large minority of people, so a threshold designed for clinic readings is set higher to allow for it. Applying the clinic number to home readings is a common and consequential mistake: it makes people think they are controlled when they are not.

The dosing-time question, which has now been answered

Take them when you will remember to take them. For several years the advice circulating was that bedtime dosing substantially reduced heart attacks and strokes, on the strength of two trials from a single research group whose effect sizes were widely judged implausible. The TIME trial then randomised 21,104 UK adults to morning or evening dosing and found no difference in cardiovascular outcomes over a median 5.2 years — hazard ratio 0.95, with a confidence interval comfortably spanning no effect.

So the practical answer is adherence, not chronobiology. The exception worth knowing is documented high night-time blood pressure, where evening dosing may still be considered — but that is a specific finding on ambulatory monitoring, not a general rule, and not something to infer from home readings.

On the recall stories

This site does not run a medicines recall ticker, and that is deliberate. Batch recalls happen regularly, are handled by manufacturers, wholesalers and your pharmacy, and are specific to particular lot numbers — so a list here would be out of date within weeks and would worry far more people than it helped. If a batch you hold is recalled, your pharmacy is the route, and the MHRA publishes drug alerts and a monthly safety roundup on GOV.UK.

What is worth carrying is regulatory change that outlasts a batch — and there is a current one. In June 2026 the MHRA required the product information for all ACE inhibitors to be updated, strengthening the warning that angioedema can appear after weeks or years of uneventful treatment, with a reminder that bradykinin-mediated angioedema does not respond to standard anaphylaxis treatment. That is not a reason to stop an ACE inhibitor. It is a reason to know that swelling of the lips, face, tongue or throat is not ruled out just because you have taken the tablet for years, and that tongue or throat swelling is a 999 call. See section 7.

What defeats treatment, in rough order of how often

  1. Doses not taken

    Roughly half of people prescribed a long-term cardiovascular drug have stopped within a year. This is the commonest reason treatment appears to fail, and the one least often said out loud — and a dose increased to cover missed doses becomes a problem the moment they are taken reliably. Combination tablets and once-daily formulations exist precisely for this.

  2. Readings that are not what they seem

    Wrong arm, wrong cuff, no rest, talking, full bladder. Several of those individually shift a reading by 10 mmHg, which is the size of a treatment decision. The technique page.

  3. Drugs and habits working against it

    Regular NSAIDs — ibuprofen and naproxen, usually bought rather than prescribed and rarely mentioned. Salt, mostly from processed food. Alcohol above a modest amount. Decongestants, liquorice, and some herbal preparations.

  4. Untreated sleep apnoea

    A common and correctable cause of blood pressure that will not come down, and one that is routinely missed. Snoring with witnessed pauses, or waking unrefreshed, is worth raising.

  5. A secondary cause

    Uncommon but not rare, and worth looking for when blood pressure stays high on three drugs including a diuretic — the definition of resistant hypertension. Primary aldosteronism is the one most often present and least often sought.

What the drugs are, how they are sequenced, and the side effects that get blamed on ageing are all in the blood pressure chapter.