Heart Medications Explained

The Timing of Cholesterol-Lowering Medications: Does Nighttime Dosing Make a Difference?

April 17, 2026

Should you take your statin at night, or does the timing not really matter? The answer depends on which statin you are on.

Nitrates for Angina: GTN Spray, Patches, and Long-Acting Tablets Explained

April 15, 2026

Key points

Nitrates are one of the oldest and most effective treatments for angina — the chest pain or tightness caused by reduced blood flow to the heart
They come in several forms: a spray or tablet under the tongue for fast relief, skin patches for all-day protection, and long-acting tablets taken once or twice daily
The most important side effect is a sudden drop in blood pressure causing headache, flushing, or dizziness — these are common and manageable, not dangerous
Nitrates must never be taken with erectile dysfunction medicines such as sildenafil (Viagra), tadalafil (Cialis), or vardenafil (Levitra) — the combination can cause a dangerous and potentially life-threatening drop in blood pressure
Tolerance can develop with long-acting nitrates — your doctor will advise a nitrate-free period each day to keep the medication working effectively

If you have been prescribed a small spray or tablet to carry with you for chest pain, you are holding one of the most effective medicines in cardiovascular care — and one with a history stretching back more than 150 years.

Nitrates have been used to treat angina since the 1870s. They remain a cornerstone of treatment today not because medicine hasn’t moved on, but because they work — quickly, reliably, and in a way that no other class of medication quite replicates. Understanding what they do, how to use them correctly, and what to watch for will help you feel confident with a medicine that may become an important part of your daily life.

What nitrates do

Angina occurs when the heart muscle is not receiving enough blood — usually because the coronary arteries that supply it have become narrowed by coronary artery disease. The heart muscle is working hard but not getting enough oxygen to meet the demand. The result is chest pain, pressure, tightness, or heaviness — often brought on by exertion and relieved by rest.

Nitrates work by relaxing the walls of blood vessels. They cause the veins throughout the body to widen — a process called vasodilation — which reduces the amount of blood returning to the heart with each beat. This reduces the workload the heart muscle has to perform, lowering its oxygen demand and relieving the mismatch between supply and demand that causes angina.

Nitrates also cause the coronary arteries themselves to relax and widen, improving blood flow to the heart muscle directly. This dual effect — reducing demand and improving supply simultaneously — is what makes them so effective.

Nitrates do not treat the underlying coronary artery disease. They manage symptoms by making the heart’s workload more manageable. This is an important distinction — and one worth discussing with your cardiologist if you are relying on them frequently.

The different types of nitrates

Nitrates come in several forms, each suited to a different purpose. Some are designed to act within minutes for immediate relief. Others release slowly throughout the day to provide ongoing protection against angina episodes.

Sublingual glyceryl trinitrate — the spray or tablet under the tongue

Glyceryl trinitrate — GTN — is the fast-acting form most people associate with angina. It comes as a small spray applied under the tongue, or as a small tablet placed under the tongue to dissolve. Both forms work within one to three minutes and last for approximately 20 to 30 minutes.

GTN is used in two ways. First, as an immediate treatment when an angina episode occurs — used at the onset of symptoms for rapid relief. Second, as a preventive measure before activities you know are likely to trigger angina — climbing stairs, walking uphill, or any exertion that has provoked symptoms before. Used this way, GTN can allow you to undertake activities that would otherwise cause discomfort.

Your cardiologist or pharmacist will give you specific instructions on how and when to use your GTN, including how many doses are appropriate and at what point you should call an ambulance rather than continuing to wait. It is important to have that conversation before you need it — so you feel confident and prepared if an episode occurs.

Your doctor or pharmacist will advise you on how many doses of GTN to use and when to stop and call an ambulance. Make sure you know this before you need it.

As a general principle, chest pain that is not relieved by GTN, is more severe than your usual angina, or is accompanied by breathlessness, sweating, or pain spreading to your arm or jaw should be treated as a potential heart attack. Call an ambulance immediately — do not drive yourself to hospital.

Australia: 000 · UK: 999 · USA/Canada: 911 · Europe: 112

Transdermal nitrate patches

Glyceryl trinitrate patches are adhesive patches applied to the skin — typically the chest, upper arm, or back — that release a steady, controlled amount of GTN through the skin over the course of the day. They are changed once daily and provide sustained protection against angina episodes throughout the wearing period.

Patches are useful for patients with frequent angina who need consistent background coverage rather than relying solely on on-demand treatment. They are applied in the morning and removed after a set number of hours — usually 12 to 14 hours — to allow a nitrate-free period overnight. This nitrate-free period is important to prevent tolerance developing.

Whether you wear your patch during the day or overnight depends on the pattern of your symptoms — your doctor is best placed to advise which timing works for you.

The site of application should be rotated daily to reduce the chance of skin irritation. Common sites include the chest wall, upper arm, shoulder, or back. Avoid areas of broken or irritated skin.

Long-acting oral nitrates

Isosorbide mononitrate and isosorbide dinitrate are oral tablets taken once or twice daily to provide longer-lasting angina protection. They are available in standard and modified-release formulations.

Isosorbide mononitrate — the more commonly prescribed of the two — is typically taken as a once-daily modified-release tablet in the morning. The modified-release formulation delivers the medication gradually throughout the day while allowing drug levels to fall overnight, preserving the nitrate-free period that prevents tolerance.

These oral nitrates are used for patients with more frequent or predictable angina where regular prevention is preferable to on-demand treatment alone. They are often prescribed alongside other angina medicines such as beta-blockers or calcium channel blockers.

Type	Form	Onset	Duration	Used for
GTN spray / tablet	Under the tongue	1–3 minutes	20–30 minutes	Immediate relief or pre-activity prevention
GTN patch	Skin patch	30–60 minutes	12–14 hours	All-day background protection
Isosorbide mononitrate	Oral tablet	30–60 minutes	Up to 24 hours (MR)	Regular daily prevention
Isosorbide dinitrate	Oral tablet	20–45 minutes	4–6 hours	Regular prevention — often twice daily

Side effects — what to expect

The most common side effects of nitrates are a direct consequence of how they work — by dilating blood vessels and lowering blood pressure. They are very common, particularly when you first start taking nitrates, and they usually ease as your body adjusts.

Headache is the most frequently reported side effect, particularly with the first few doses. The same vasodilation that relieves angina also widens the blood vessels in the scalp, causing a throbbing headache. For most patients this improves significantly within a few days as the body adapts. Paracetamol can be taken to manage the headache in the meantime. If headaches are severe or persistent, speak to your doctor — adjusting the dose or switching formulation often helps.

Flushing and warmth — a feeling of heat or redness in the face — is also common and has the same vascular mechanism as the headache. It is temporary and harmless.

Dizziness and light-headedness occur because nitrates lower blood pressure. Sitting or lying down when using GTN spray significantly reduces this risk. Standing up quickly after taking a nitrate — particularly after exercise or in warm weather — can cause a more pronounced drop in blood pressure.

Tolerance — the gradual reduction in effectiveness with regular use — is specific to long-acting nitrates and patches. It does not occur with occasional use of GTN spray. To prevent tolerance, long-acting nitrates are prescribed with a structured nitrate-free period each day, usually overnight, during which the body resets its sensitivity to the medication. Your doctor will advise on the specific timing for your prescription.

Headache with the first dose of GTN is very common — for most patients it improves significantly within days as the body adjusts
British Heart Foundation — Nitrate medicines guidance

The critical interaction with erectile dysfunction medicines

This is the most important safety message associated with nitrate medicines — and one that every patient taking nitrates needs to know clearly.

Nitrates must never be taken within 24 to 48 hours of erectile dysfunction medicines — including sildenafil (Viagra, Revatio), tadalafil (Cialis), vardenafil (Levitra), and avanafil (Spedra). These medicines belong to a class called PDE5 inhibitors and they work by a related mechanism to nitrates. When taken together, the two drugs cause an additive and potentially catastrophic drop in blood pressure — severe hypotension that can cause fainting, heart attack, stroke, or death.

This interaction applies regardless of the dose of either medication and regardless of the time gap — the window of risk with tadalafil (Cialis) extends to 48 hours due to its longer duration of action.

This is not a reason to avoid discussing sexual health with your cardiologist. Erectile dysfunction is common in men with cardiovascular disease and is itself an important cardiovascular risk marker. There are approaches to managing both conditions safely — but the conversation needs to happen with your doctor, not by managing it yourself. If you are taking nitrates and have questions about sexual activity or erectile dysfunction, please raise it at your next appointment.

Other important cautions

Low blood pressure. Nitrates should be used with caution if your blood pressure is already low. If you feel very dizzy or faint after taking GTN, sit or lie down immediately and inform your doctor.

Aortic stenosis. Patients with significant narrowing of the aortic valve — aortic stenosis — may not tolerate nitrates well, as their heart depends on maintaining adequate filling pressure. Your cardiologist will advise you specifically if this applies to your situation.

Hypertrophic cardiomyopathy. Similarly, nitrates may worsen symptoms in some patients with hypertrophic cardiomyopathy — a condition where the heart muscle is thickened. Always confirm with your specialist whether nitrates are appropriate for you.

Alcohol. Alcohol enhances the blood pressure-lowering effect of nitrates and increases the risk of dizziness and faintness. Take care with alcohol consumption while on nitrate medicines.

Other blood pressure medicines. Nitrates add to the blood pressure-lowering effects of other antihypertensives, including ACE inhibitors, ARBs, beta-blockers, and calcium channel blockers. This combination is often intentional and beneficial — but worth being aware of in terms of dizziness risk, particularly on standing.

Practical tips for taking nitrates

Keep your GTN spray with you at all times. It is of no use at home if you need it while out. Many patients keep one spray in their pocket or bag and a second at home.

Check the expiry date. GTN spray and tablets have a limited shelf life and lose potency over time. Check the expiry date regularly and replace as needed.

Store correctly. GTN is sensitive to light and heat. Keep it in its original container, away from direct sunlight and warm environments. Do not store in a car glovebox in warm climates.

Know when to use it preventively. If you know that a particular activity tends to trigger your angina — climbing stairs, walking to the car in cold weather — using a dose of GTN two to three minutes before that activity can prevent the episode rather than treat it.

Tell all your doctors and pharmacists. Always inform any healthcare professional prescribing a new medicine that you are taking nitrates, so that interactions — particularly with blood pressure medicines — can be checked.

Heart Matters Resource

If your GTN is not working

If your chest pain is not relieved by GTN, is more severe than usual, or is accompanied by breathlessness or pain spreading to your arm or jaw — call an ambulance immediately. Do not drive yourself to hospital.

Read: Chest Pain — Causes and When to Seek Help →

Conclusion

Nitrates are a remarkably effective class of medicine — fast-acting, well-understood, and with a track record measured in decades. Knowing how to use your GTN spray correctly, understanding the difference between on-demand and preventive use, and being aware of the critical interaction with erectile dysfunction medicines will allow you to use these medicines safely and confidently.

If your angina symptoms are changing — becoming more frequent, occurring at rest, or requiring more GTN than usual — that is a signal to speak with your cardiologist rather than simply increasing your nitrate use. Changing symptom patterns deserve reassessment, not just more medication.

Used well, nitrates give you genuine control over a condition that can otherwise feel unpredictable. That is worth understanding clearly.

Statins: What Patients Ask Me Most

April 17, 2026April 15, 2026

Key Points

Statins are among the most prescribed medications in the world — and among the most stopped without anyone being told.
Most of what circulates online about statins is negative. The clinical evidence tells a more balanced story.
Statins do more than lower cholesterol — in people at genuine cardiac risk, research shows they stabilise vulnerable plaques and reduce the inflammatory process that triggers heart attacks.
Side effects are real and should never be dismissed. Muscle aches, fatigue, and memory concerns deserve a proper conversation with your doctor — and there are options.
Not everyone needs a statin. For those prescribed one after a cardiac event or because of genuinely high risk, the evidence for staying on it is strong.

I hear some version of this almost every week in clinic. A patient sits down, and somewhere in the conversation they mention — sometimes apologetically — that they have stopped their statin. Or they are thinking about stopping it. Or they started it and felt different, and nobody ever explained why they were on it in the first place.

I understand this completely. The conversation around statins in the lay media and on social media is overwhelmingly negative. Muscle pain, memory loss, fatigue, “I haven’t felt like myself since I started.” These are real experiences, and they deserve to be taken seriously — not brushed aside with a blanket reassurance that statins are safe.

What I want to do here is share the conversation I try to have in clinic: honest, balanced, and grounded in what the evidence actually shows.

What a Statin Actually Does

Most patients are told their statin lowers cholesterol. That is true — but it is a bit like saying a seatbelt stops you moving forward. Technically accurate, but it misses what matters.

The more important action of a statin — particularly for someone who has already had a heart attack or has significant coronary artery disease — is what it does to the plaques inside the artery wall.

Let me explain what I mean by that.

The Plaque Story — What Is Actually Happening Inside

Cross-section illustration of a coronary artery showing a lipid-rich plaque with inflammatory cells, alongside an actual OCT image from Prof. Peter Barlis's PhD thesis showing the view from inside a coronary artery

Left: an illustration of a coronary artery cross-section showing a lipid-rich plaque with inflammatory cells at the fibrous cap. Right: an actual OCT image from my PhD thesis — the view from inside a coronary artery, with the dark region indicating a lipid pool beneath the vessel wall.

I often show patients this image in clinic. On the left is an illustration of what a vulnerable plaque looks like in cross-section — the open vessel with blood flowing through it, and beneath the surface, a pool of soft, lipid-rich material. You can see the grey star-shaped cells sitting right at the boundary between the plaque and the vessel lining. Those are macrophages — inflammatory cells that have migrated into the plaque and are, in a sense, destabilising it from within.

On the right is a real image — from my own PhD research using a technology called optical coherence tomography, or OCT, which involves threading a tiny light-based probe inside a living coronary artery. The bright golden ring is the artery wall. The dark shadow at the bottom is exactly what it looks like on the illustration: a lipid pool sitting just beneath the surface, visible in extraordinary detail from inside the vessel itself.

The thin layer of tissue covering that lipid pool is called the fibrous cap. In a vulnerable plaque, this cap is thin and fragile — and those inflammatory cells are actively weakening it further. When the cap ruptures, the lipid-rich contents spill into the bloodstream. A clot forms almost instantly. Depending on how large that clot is, and which artery is involved, the result is either a smaller heart attack — what we call an NSTEMI — or a complete blockage and a larger event, an STEMI.

This is what most heart attacks actually are. Not a gradual narrowing that finally closes off. A rupture. A sudden event triggered by a plaque that may not have been causing any symptoms at all.

Where Statins Come In

Here is what changes the conversation for me, and what I explain to every patient who asks why they need to stay on their statin.

Statins stabilise vulnerable plaques. They reduce the inflammatory cells infiltrating the cap — those macrophages that are weakening it from within. Over time, research shows they can thicken the fibrous cap itself, making it more resistant to rupture. They change the biology of the plaque, not just the number on a blood test.

This is why, in patients who have already had a heart attack or who have established coronary disease, the evidence for statins is so compelling. It is not primarily about the LDL number. It is about reducing the likelihood that a vulnerable plaque will rupture and cause another event. This is also the reason the relationship between statins and your calcium score is more nuanced than it first appears.

~25%
Reduction in major cardiovascular events with high-intensity statin therapy in high-risk patients — regardless of starting cholesterol level
Cholesterol Treatment Trialists’ (CTT) Collaboration meta-analyses

Who Actually Needs a Statin?

This is where I want to be direct: not everyone does.

There is a legitimate conversation to be had about patients who have been started on a statin primarily because a cholesterol number crossed a threshold — without a proper discussion of their individual cardiovascular risk, their age, their other risk factors, and what the medication is actually expected to achieve for them personally.

If you were prescribed a statin and never had a proper conversation about why, that is worth revisiting with your GP or cardiologist. Cardiovascular risk calculators — used by doctors worldwide — look at the full picture: age, blood pressure, smoking status, family history, and cholesterol together. The number on its own tells only part of the story. Emerging tools like the hs-CRP test and imaging such as the coronary calcium score can add further context in the right patient.

Where the evidence is clearest and most compelling is in people who have already had a cardiac event, those with established coronary artery disease, and those at genuinely high cardiovascular risk. For these patients, the benefit of staying on a statin is well established and significant.

Questions Patients Ask Me Most

These are the questions I hear most often in clinic — answered as honestly as I can. As always, these are for general information, and any decision about your own medication should be made in conversation with your doctor.

Will statins damage my muscles?

Mostly reassuring

Muscle discomfort affects around 5–10% of people on statins. Serious muscle damage is genuinely rare. Significant pain, weakness, or dark urine should prompt a call to your doctor — but general aching is often manageable with a dose change or switch to a different statin, which your doctor can discuss with you.

Can statins affect my memory?

Mostly reassuring

The overall evidence does not support a link between statins and dementia or significant cognitive decline. Some people notice a change in mental clarity — an experience that deserves investigation, not dismissal. This is worth raising with your doctor rather than simply stopping the medication.

Do I really need one if I feel fine?

Worth discussing

Not everyone does. If a statin was started purely because a number crossed a threshold — with no discussion of individual risk — that conversation is worth revisiting with your GP. For people who have had a cardiac event or have established coronary disease, the evidence is strong regardless of how they feel.

Can I take a break from my statin?

Please discuss first

This is a conversation to have with your doctor before making any change. Many people quietly stop and never mention it — but in those with coronary artery disease or a prior heart attack, statins are doing something important beyond lowering a number. There are almost always options if the current medication is not suiting you.

Are there alternatives if I can’t tolerate statins?

Yes — options exist

Every-other-day dosing works well for many people who experience daily side effects. Switching to a different statin often resolves muscle symptoms. Ezetimibe is a well-tolerated tablet that lowers cholesterol through a different mechanism and is often used alongside or instead of a statin. For high-risk patients who cannot tolerate statins at all, PCSK9 inhibitors are a highly effective option. All of these alternatives are best discussed with your doctor before making any changes.

Does it matter which statin I’m on?

Yes — they differ

Statins vary in potency and side effect profile. Rosuvastatin (Crestor) and atorvastatin (Lipitor) are the most potent. Some people tolerate one significantly better than another. If side effects are an issue, the answer is often a switch or dose adjustment — a discussion worth having with your doctor before considering stopping altogether.

Should I take my statin in the morning or at night?

It depends on the statin

There are some differences between statins, and timing can play a small role — but the most important factor is consistency. Taking it at the same time each day matters more than which hour is chosen. For a fuller explanation of the pharmacology behind this, see our article on the timing of cholesterol-lowering medications. Your doctor is best placed to advise on what suits your particular medication and routine.

Can I lower my cholesterol naturally?

Worth discussing

Many products claim to lower cholesterol naturally — most have not been tested in proper clinical trials, and caution is warranted. Two approaches with reasonable evidence behind them are plant sterols and a generous fibre intake. A Mediterranean-style diet remains the most well-studied dietary pattern for cardiovascular risk. None of these replace a statin when one is clinically indicated, but they can be meaningful complements. Any supplement addition is worth discussing with your doctor first.

The Side Effects — Taking Them Seriously

Muscle aches and pains are the most commonly reported side effect, and they are real. Roughly 5–10% of people on statins experience some degree of muscle discomfort — though true muscle damage (myopathy) is considerably rarer.

What is also real is the nocebo effect — the phenomenon where knowing a medication might cause symptoms makes those symptoms more likely to be noticed and attributed to it. Large blinded trials have shown that many people who report muscle symptoms on statins experience the same symptoms on placebo. That does not mean the symptoms are not real — it means the relationship between statins and those symptoms is more complex than it first appears.

Memory and cognitive concerns are raised frequently — and understandably, given how much has been written about them. The overall evidence does not support a causal link between statins and dementia or significant cognitive decline. Some people do notice a change in mental clarity when starting a statin, and this deserves investigation rather than dismissal.

My strong view is this: side effects should never simply be accepted. There are several different statins, they vary in their potency and their side effect profiles, and some people tolerate one far better than another. Dose adjustments matter. Every-other-day dosing works well for some patients. And if a statin genuinely cannot be tolerated, there are alternative lipid-lowering options — including ezetimibe and PCSK9 inhibitors — that achieve excellent results. All of this is a conversation to have with your doctor.

If you are experiencing side effects on your statin, the conversation with your doctor is always worth having before stopping. There is almost always something that can be tried.

What I Tell My Patients

When a patient comes to me having stopped their statin because of something they read online, I don’t argue with them. I show them the image above — the plaque, the cap, the inflammatory cells — and I explain what the evidence shows about what these medications actually do inside the artery wall. Most of the time, that conversation changes things.

Conclusion

Statins are not perfect medications, and the decision to take one — or stay on one — deserves a proper, individual conversation. Not every person with a mildly elevated cholesterol needs a statin, and side effects should never be dismissed or simply tolerated.

But for those with established heart disease or genuinely high risk, the evidence is clear: statins do something that no other medication currently does as well. They get inside the artery wall and stabilise the plaques that cause heart attacks. That is worth understanding — and worth a conversation before making a decision either way.

If you have questions about your statin, or you have stopped taking it and haven’t told your doctor, please bring it up at your next appointment. There are options, and the conversation is always worth having.

This article provides general information only and is not medical advice. Any decisions about your medications should be made in conversation with your cardiologist, GP, or pharmacist.

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Medications

The Timing of Cholesterol-Lowering Medications: Does Nighttime Dosing Make a Difference?