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HIGH BLOOD PRESSURE SERIES · ARTICLE 9 OF 12
Blood pressure medications
The main groups, the side effects, and why so many people stop taking them.
If you have followed the series up to here, you have already made the changes that lower BP without tablets — food, salt, walking, sleep, stress. For some people, this is enough. For most South Africans with Stage 2 BP, and many with Stage 1, medication will still be part of the picture. The good news: BP medications are some of the best-studied, longest-used, cheapest, and most effective drugs in medicine.
This article walks through the five main groups of BP tablets in plain English. What each one is actually doing inside you. Who tends to be put on which. The common side effects, what they feel like, and what to do about them. Why most South Africans end up on two tablets rather than one. And the single biggest mistake people make — stopping the tablets when they feel fine.
Important note
This article describes how the main BP drug groups work. It is not personal medical advice and it does not replace a prescription. Specific drug choice, dose, and combination should always be made with your clinic nurse, doctor or pharmacist, who knows your full picture.
Why medication, when food and walking can lower BP?
Lifestyle changes are powerful — typically 10 – 15 mmHg combined, sometimes more. But:
• Some people start at very high numbers. A Stage 2 BP of 170 / 105 needs to come down by 40 – 50 mmHg, which is beyond what lifestyle alone can usually do.
• Some people have other conditions — diabetes, kidney disease, heart trouble — that mean tighter targets and faster results matter more.
• Some people have a stronger genetic push toward high BP than lifestyle can fully counter.
• And — most importantly — medication doesn’t replace the lifestyle changes. The two together give the best result. Medication is the parachute. Lifestyle is the wing.
The five main groups
Modern BP treatment uses five main families of drug, each working in a different way. They are often combined, because two drugs at small doses give a bigger result with fewer side effects than one drug at a high dose.
1. ACE inhibitors
2. ARBs (angiotensin receptor blockers)
3. Calcium channel blockers
4. Diuretics (“water tablets”)
5. Beta-blockers
Almost everyone with high BP in South Africa ends up on one or more of these. They are all on the South African Essential Medicines List, which means they are available free at public clinics for patients who qualify, and inexpensive in the private sector.
1. ACE inhibitors
“-PRIL” ENDINGS
EXAMPLES
Enalapril, lisinopril, perindopril, captopril
WHAT IT DOES
Blocks a chemical pathway (the renin-angiotensin system) that constricts blood vessels and tells the kidneys to hold onto salt. Net effect: arteries relax, kidneys flush a little salt, BP drops.
GOOD FOR
Younger and middle-aged adults, anyone with diabetes (it protects the kidneys), anyone with heart failure, anyone with kidney disease.
COMMON SIDE EFFECTS
A dry, persistent cough (about 1 in 10 people) — feels like a tickle in the throat that doesn’t go away. Mild dizziness in the first week. A small rise in potassium.
IF YOU HAVE SIDE EFFECTS
The cough doesn’t usually go away on its own. If it bothers you, ask your clinic to switch you to an ARB (next group) — same benefit, no cough.
SA AVAILABILITY
Free at public clinics. R30 – R80/month at private pharmacies for the generic.
2. ARBs — angiotensin receptor blockers
“-SARTAN” ENDINGS
EXAMPLES
Losartan, telmisartan, valsartan, irbesartan
WHAT IT DOES
Same target as ACE inhibitors but a different point on the pathway. Same end result — arteries relax, BP drops. No cough.
GOOD FOR
Same groups as ACE inhibitors — diabetes, kidney protection, heart failure — especially useful if an ACE inhibitor caused a cough.
COMMON SIDE EFFECTS
Mild dizziness in the first week. A small rise in potassium. Generally one of the best-tolerated BP drug groups.
IF YOU HAVE SIDE EFFECTS
The dizziness usually settles within a week or two. If it doesn’t, your clinic can lower the dose or split the tablet across the day.
SA AVAILABILITY
Free at public clinics (losartan is standard). R40 – R100/month at private pharmacies for generics.
3. Calcium channel blockers
“-DIPINE” ENDINGS (MOSTLY)
EXAMPLES
Amlodipine, nifedipine (long-acting), felodipine, diltiazem, verapamil
WHAT IT DOES
Blocks calcium from entering the smooth muscle cells in the artery walls. Less calcium in the muscle means the artery walls relax. Wider arteries, lower pressure.
GOOD FOR
Older adults, Black South Africans (the evidence is particularly strong here), people with isolated high systolic BP, people who can’t tolerate ACE inhibitors or ARBs.
COMMON SIDE EFFECTS
Swollen ankles by the end of the day (about 1 in 8 people on amlodipine — annoying, not dangerous). Mild flushing. Constipation, especially with verapamil. Occasionally gum overgrowth — a reason to mention these tablets to your dentist.
IF YOU HAVE SIDE EFFECTS
Ankle swelling responds to: putting your feet up at the end of the day, walking (article 7), or switching to a different drug. If swelling is severe, ask your clinic.
SA AVAILABILITY
Free at public clinics (amlodipine is standard). R20 – R60/month at private pharmacies for the generic.
4. Diuretics — “water tablets”
“FLUSH OUT SALT”
EXAMPLES
Hydrochlorothiazide (HCTZ), indapamide, chlorthalidone, furosemide (Lasix — used for heart failure rather than BP on its own)
WHAT IT DOES
Tells the kidneys to flush out a small amount of salt and water. Less fluid in the system means less pressure pushing on the artery walls.
GOOD FOR
Almost everyone with high BP. Particularly useful in combination with another drug. Cheap and effective.
COMMON SIDE EFFECTS
Needing to pass urine more often in the first few weeks — this settles. A small drop in potassium (your clinic may check blood levels). Slightly higher risk of gout in people who already had it. Mild dizziness from standing up too fast in the first week.
IF YOU HAVE SIDE EFFECTS
Take the tablet in the morning, not at night, so the bathroom trips don’t disrupt sleep. Eat a banana a day (article 5) to balance the potassium. Stand up slowly for the first week.
SA AVAILABILITY
Free at public clinics. R15 – R40/month at private pharmacies for the generic.
5. Beta-blockers
“-LOL” ENDINGS
EXAMPLES
Atenolol, bisoprolol, carvedilol, metoprolol, propranolol
WHAT IT DOES
Blocks the stress hormone receptors on the heart. The heart beats slower and less forcefully, so less blood is pumped out with each beat — and BP drops.
GOOD FOR
People with high BP who also have angina, a previous heart attack, certain heart-rhythm problems, or who are very anxious. Less commonly used as a first-line BP drug today than 20 years ago.
COMMON SIDE EFFECTS
Tiredness, especially during exercise (your heart can’t speed up as easily). Cold hands and feet. Vivid dreams. Slight weight gain. In some men, reduced sex drive.
IF YOU HAVE SIDE EFFECTS
If exercise tolerance is the issue, talk to your clinic about switching to a newer beta-blocker like bisoprolol or carvedilol, or to a different drug group entirely. Don’t stop suddenly — beta-blockers should always be tapered down over a couple of weeks.
SA AVAILABILITY
Free at public clinics (atenolol and carvedilol are standard). R25 – R70/month at private pharmacies.
Why most people end up on more than one tablet
Most people with high BP, by year two of treatment, are on two drugs. About a third are on three. This is not a failure or a sign that things are worse. It is how modern BP treatment works.
The reasoning is simple. Each drug group works on a different part of the BP system. Two drugs at low doses, working on two different parts, bring BP down more than one drug at a high dose. They also cause fewer side effects, because each dose is smaller.
Standard South African combinations include:
• ACE inhibitor or ARB + calcium channel blocker — particularly for diabetics and Black South Africans
• ACE inhibitor or ARB + diuretic — particularly for middle-aged adults
• Calcium channel blocker + diuretic — particularly for older adults
• Three of the above — for people whose BP is hard to control on two
Many of these combinations are available in a single tablet, which makes them easier to take. Ask your clinic if a combination tablet might suit you.
The “single pill” advantage
South African public clinics increasingly use fixed-dose combination tablets — two BP medications packed into one pill, taken once a day. The two main reasons: people are more likely to remember to take one tablet than two, and the dose of each drug is smaller so side effects are less likely. If you are juggling three or four tablets a day, ask whether your combination is available as a single pill.
The “but I feel fine” trap
This is the place where, in our experience, more South Africans fail their BP treatment than anywhere else.
You start a tablet. Your BP comes down. You feel exactly the same — because you felt fine before, and you feel fine now. After a month or two, the daily tablet starts to feel pointless. You skip a day. Nothing happens. You skip a week. Still nothing. So you stop.
Within two to four weeks of stopping, your BP creeps back up to where it was. You still feel fine. The arteries are still stiffening, the kidneys are still being damaged, the heart is still working harder than it should — but you can’t feel any of that. Ten or twenty years later, the body finally complains, in the form of a stroke or a heart attack. By that point, the choice was made years earlier — by whether or not you took the tablet every day.
BP medication is for life. Not for “until you feel better”. For life.
That can feel heavy when you first hear it. But it should also be reassuring: you are not on these tablets because something is going wrong day to day. You are on them because they are working — quietly, in the background — to protect the body in twenty years’ time.
How to take BP medication well
• Take it at the same time every day. Most people choose morning, with breakfast. Whichever time you choose, stick to it.
• If you miss a dose, take it as soon as you remember. Unless it is nearly time for the next dose — in which case skip the missed one. Never double up.
• Keep a small supply ahead. Don’t be down to your last tablet before you collect your next month. Many people miss doses because of clinic queues or pharmacy stock-outs, not because they meant to.
• Use a pill organiser. The little 7-day plastic box that costs R30 at any pharmacy is the cheapest piece of medical equipment that makes the biggest difference to BP control.
• Take your home BP readings. Article 4. The numbers are how you and your clinic know whether the dose is right.
• Don’t stop on your own. If you want to come off a tablet, talk to your clinic first. Most BP drugs are safe to stop suddenly, but a few (beta-blockers especially) should be tapered.
Side effects — what to expect, when to call
Most BP side effects are mild and pass within the first two weeks as your body adapts to the new chemistry. Things to know:
Common, usually settles within 2 weeks
• Mild dizziness or light-headedness when standing up quickly
• Needing to pass urine more often (if on a diuretic)
• Mild headache
• Tiredness for the first few days
Persistent — worth a clinic visit but not urgent
• A dry cough that won’t go away (ACE inhibitors)
• Swollen ankles by the end of every day (calcium channel blockers)
• Tiredness or cold hands and feet that don’t pass (beta-blockers)
• Constipation (some calcium channel blockers)
• Reduced sex drive
• Vivid or disturbing dreams
For any of these, don’t stop the tablet on your own. Call or visit your clinic — there is almost always another drug in another group that will give you the same BP control without the side effect that is bothering you.
Go to a clinic the same day if you have
Severe dizziness or fainting.
Swelling of the face, lips or tongue (very rare but serious, particularly with ACE inhibitors).
A new severe headache or chest pain.
A heart rate consistently below 50 beats a minute (if on a beta-blocker).
Severe ankle swelling, particularly with shortness of breath — possible heart failure.
Drug interactions to know about
A few common things can interfere with BP medication or push BP up despite the tablets:
• NSAIDs — anti-inflammatory painkillers like ibuprofen, diclofenac (Voltaren), and the regular use of Mybulen. These raise BP and reduce the effect of most BP tablets. Paracetamol (Panado) is fine. If you need an anti-inflammatory regularly, talk to your clinic.
• Decongestants — anything with pseudoephedrine (in many cold and flu remedies). These raise BP and can dangerously interact with BP medication. Look for “high blood pressure” warnings on cold and flu packaging.
• Cortisone — both prescription steroids and the cortisone creams that some people use long-term can raise BP.
• Some herbal remedies — particularly liquorice root and certain traditional medicines. If you use traditional medicine, mention it to your clinic. There is no shame in this — there is just a real interaction risk that needs to be known.
• Salt substitutes (article 6) — fine for most people, but not safe alongside ACE inhibitors or ARBs in people with kidney problems. Ask your clinic before switching.
What if my BP still isn’t coming down?
Sometimes BP stays high even on two or three tablets. Before deciding the medication isn’t working, your clinic will usually check:
• Are you actually taking the tablets every day? The most common reason BP doesn’t respond is missed doses. There is no shame in being honest about this — it is fixable. Pretending things are fine when they aren’t is what loses people their kidneys and their eyes.
• How much salt are you still eating? Article 6.
• Are you drinking heavily? Article 8.
• Are you taking NSAIDs regularly?
• Is there an underlying cause? Sleep apnoea, narrowing of the kidney arteries, certain hormonal conditions, and a few other things can keep BP high. Your clinic may run extra tests.
• Are you on the right combination? Sometimes simply swapping one drug for another in the same group, or adding a fourth, brings BP down within weeks.
“Resistant” hypertension — BP that won’t come down on three tablets — affects about 1 in 10 patients. There are good options for it. None of them are giving up.
The bigger picture
BP medication has a reputation for being unpleasant, side-effect-heavy, and lifelong — which is part true. It is lifelong. But the side effects are usually mild, usually pass, and almost always have a workaround. The tablets are some of the cheapest in medicine, available free at public clinics, and they prevent the things in article 3 — stroke, heart attack, kidney failure, dementia.
If you remember one thing from this article, let it be this: the tablets work in the background, every day, even when you feel fine. The feeling fine is the medication doing its job. Stopping the tablets does not undo the high BP — it just hides the warning sign until something serious happens.
The next article in the series covers the deadly duo — high blood pressure and diabetes, the two most common chronic conditions in South Africa, how they amplify each other, and what an integrated approach looks like.
Where to get more help
Your nearest public clinic — for free prescriptions, monthly refills, and questions about side effects. The clinic pharmacist is one of the best resources for medication questions.
Your community pharmacist — even if your medication is from a public clinic, any retail pharmacist will explain side effects, interactions and timing for free.
South African Hypertension Society — hypertension.org.za — patient resources and treatment guidelines.
Heart and Stroke Foundation South Africa — heartfoundation.co.za · 021 422 1586.
Phila Today High Blood Pressure Series — next: high blood pressure and diabetes — the deadly duo.
Phila Today · Article 9 of 12 in the High Blood Pressure Series