Sildenafil Teva
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If you are wondering whether Viagra affects blood pressure, the short answer is that Viagra (sildenafil) does not usually raise blood pressure. It can cause a small, temporary reduction in blood pressure instead. After a 100mg dose, the product information reports an average maximum reduction of about 8.4 mmHg in systolic blood pressure and 5.5 mmHg in diastolic blood pressure.
For some people with well controlled high blood pressure, sildenafil may be suitable following an appropriate clinical assessment. However, having high blood pressure does not automatically mean that sildenafil is suitable for you. Your other medicines, cardiovascular health, blood pressure readings and medical history all need to be considered.
This guide explains how sildenafil can affect blood pressure, which blood pressure readings may require extra caution, which blood pressure medicines can interact with it and when sildenafil should not be used. The most important interaction is with nitrates, where the combination can cause a potentially dangerous fall in blood pressure.
The figures in this guide are based on the approved sildenafil product information and should be considered alongside individual medical advice.
Key things to know
- Sildenafil can lower blood pressure slightly. It is not used to treat high blood pressure.
- After a 100mg dose, the product information reports a mean maximum reduction of about 8.4 mmHg in systolic blood pressure and 5.5 mmHg in diastolic blood pressure. This effect is temporary.
- Sildenafil must not be taken with nitrate medicines or recreational nitrites known as poppers because the combination can cause a significant and potentially dangerous fall in blood pressure.
- Many other blood pressure medicines can be used with sildenafil, but the combination may cause an additional reduction in blood pressure. Your prescriber should check your medicines before treatment.
- The product information notes that there are no controlled clinical data for sildenafil in people with blood pressure above 170/110 mmHg or resting blood pressure below 90/50 mmHg. Extra caution may therefore be needed in these situations.
- Sildenafil is not a treatment for high blood pressure and should not be used instead of prescribed blood pressure medicine.
Does Viagra Raise or Lower Blood Pressure?
Sildenafil can lower blood pressure slightly. It does not normally raise blood pressure or cause hypertension.
The reason is linked to how sildenafil works. Sildenafil, the active ingredient in Viagra, inhibits an enzyme called PDE5. This slows the breakdown of a messenger called cyclic GMP (cGMP), which helps relax smooth muscle.
PDE5 is also found in blood vessels outside the penis. By inhibiting this enzyme, sildenafil can cause some widening of blood vessels throughout the body. This can lead to a small reduction in blood pressure.
The measured effect
In healthy volunteers, a single 100mg oral dose of sildenafil produced a mean maximum reduction in resting systolic blood pressure of 8.4 mmHg and a corresponding reduction in diastolic blood pressure of 5.5 mmHg. The reductions were temporary and occurred around the time when sildenafil reached its peak concentration in the blood.
For most people, this represents a relatively modest change in blood pressure. However, the effect can be more important when sildenafil is taken alongside other medicines or substances that also lower blood pressure.
In a study involving 14 patients with severe coronary artery disease, defined as more than 70 per cent narrowing in at least one coronary artery, a single 100mg dose reduced mean resting systolic and diastolic blood pressure by about 7 per cent and 6 per cent respectively. These results came from a small study population and should not be assumed to apply to everyone.
So why does blood pressure come up so much?
The main concern is not usually sildenafil on its own. The concern is what can happen when its blood pressure lowering effect is combined with another medicine or substance that also lowers blood pressure.
For example, sildenafil must not be taken with nitrate medicines because both affect the nitric oxide and cyclic GMP pathway. Together, they can cause a severe drop in blood pressure.
Other blood pressure medicines may also have an additive effect, although the reduction is generally more modest. This is why your prescriber should know about all the medicines and supplements you take before recommending sildenafil.
If you have high blood pressure, heart disease or take regular blood pressure medication, speak with your prescriber before using sildenafil. They can assess your individual circumstances and check whether treatment is appropriate.
Can You Take Viagra With High Blood Pressure?
In many cases, people with high blood pressure may be able to take sildenafil, provided their blood pressure and overall health have been assessed and their current medicines have been reviewed by a healthcare professional. Having high blood pressure on its own does not automatically mean that sildenafil is unsuitable.
There are two important things to consider before treatment. First, your prescriber needs to check the medicines you take because some combinations can cause a significant drop in blood pressure. Second, your cardiovascular health needs to be considered, including whether sexual activity is safe for you.
Sexual activity can place physical demands on the cardiovascular system. If you have unstable angina, poorly controlled heart failure or another serious cardiovascular condition, the main concern may be the physical strain of sexual activity as well as the effects of sildenafil.
If you have high blood pressure or a heart condition, speak with your prescriber before using sildenafil. They can assess your individual circumstances and advise whether treatment is appropriate.
What blood pressure is considered too high for Viagra?
There is no single blood pressure reading that automatically means sildenafil is unsuitable for everyone. The decision depends on your overall health, medical history, cardiovascular risk and other medicines.
The sildenafil product information states that there are no controlled clinical data on safety or effectiveness in people with certain blood pressure readings, including those with blood pressure above 170/110 mmHg. It also advises caution when prescribing sildenafil to people in these groups.
If your blood pressure is very high or not well controlled, it is important to discuss this with your healthcare professional before taking sildenafil rather than relying on a blood pressure number alone.
| Group with no controlled safety data | What this means in practice |
|---|---|
| Blood pressure greater than 170/110 mmHg | Markedly raised pressure. The usual approach is to get blood pressure better controlled first rather than to treat the two problems in parallel |
| Resting hypotension below 90/50 mmHg | Blood pressure already low enough that a further fall could cause fainting |
| Myocardial infarction, stroke or life-threatening arrhythmia within the last 6 months | Recent major cardiovascular event; specialist input is usually needed |
| Cardiac failure, or coronary artery disease causing unstable angina | Both the medicine and sexual activity itself need assessing by a clinician who knows the case |
Note the wording carefully. These are situations where clinical evidence is limited and extra caution may be needed. They are not automatically a refusal list. Whether sildenafil is suitable is a decision for a prescriber, based on your blood pressure readings, medical history, cardiovascular health and other medicines.
If you do not know your current blood pressure, it can be useful to have it checked before discussing treatment. Blood pressure checks may be available through pharmacies, GP surgeries and other healthcare services in the UK. Knowing your current reading can help your healthcare professional make a more informed assessment.
Can Viagra Be Used to Treat High Blood Pressure?
No. Sildenafil is not licensed to treat systemic high blood pressure, also known as hypertension. It should not be used as a replacement for prescribed blood pressure medicine.
The confusion is understandable because sildenafil was originally investigated as a possible treatment for angina. The results were not sufficient to support its development for that use. Sildenafil was later developed for erectile dysfunction.
Sildenafil is also the active ingredient in Revatio, which is licensed for pulmonary arterial hypertension. Pulmonary arterial hypertension is different from the high blood pressure measured with a blood pressure cuff. It affects the blood vessels between the heart and lungs and is treated differently, including with different dosing under appropriate medical supervision.
If you take medicine for high blood pressure, continue taking it as prescribed. Do not stop, reduce or skip your blood pressure medicine because you are considering or taking sildenafil. If you think your blood pressure treatment may be affecting your erections, speak with your prescriber. They can review your treatment and consider whether an alternative may be appropriate.
Viagra and Blood Pressure Tablets: Which Combinations Actually Matter
This is where the important safety information comes in. Some medicines that affect blood pressure can be used alongside sildenafil with appropriate medical assessment, while others can cause a serious interaction and must not be combined with it.
The most important interaction is with nitrates and nitrate like medicines, because combining them with sildenafil can cause a significant and potentially dangerous fall in blood pressure.
Nitrates and nitrate like medicines: the absolute bar
Sildenafil must not be taken with nitrate medicines or recreational nitrites known as poppers. This includes medicines such as glyceryl trinitrate (GTN), isosorbide mononitrate and isosorbide dinitrate. Nicorandil, which is used to treat angina and has nitrate activity, is also contraindicated with sildenafil.
Riociguat, a soluble guanylate cyclase stimulator used for certain forms of pulmonary hypertension, is another medicine that must not be combined with sildenafil because of the risk of a significant fall in blood pressure.
The reason is linked to the same nitric oxide and cyclic GMP pathway involved in sildenafil's action. Nitrates increase nitric oxide activity and raise cyclic GMP levels, while sildenafil slows the breakdown of cyclic GMP. When these effects are combined, blood pressure can fall significantly.
For this reason, the combination is contraindicated and should not be used. If you use a GTN spray or another nitrate, even occasionally, tell your prescriber before discussing sildenafil. Medicines that are used only from time to time can be easy to overlook during a consultation, but they are still important for your safety.
Alcohol can also increase the likelihood of dizziness or light headedness with sildenafil in some people. If you are taking medicines that lower blood pressure, it is sensible to discuss your alcohol intake with your healthcare professional.
Alpha blockers: the group that needs extra care
Alpha blockers such as doxazosin, tamsulosin and alfuzosin are commonly used for prostate symptoms and, in some cases, high blood pressure. They lower blood pressure through a different mechanism from sildenafil. Taking them together can add to the blood pressure lowering effect and may cause dizziness, light headedness or a drop in blood pressure when standing, particularly in some people.
The effect can vary from person to person. In clinical studies involving men with benign prostatic hyperplasia who were already taking doxazosin, adding sildenafil resulted in additional reductions in blood pressure.
Because of this potential interaction, your prescriber should know if you take an alpha blocker before sildenafil is prescribed. They may consider your current dose, blood pressure, other medicines and how well you tolerate the alpha blocker when deciding whether sildenafil is appropriate. Do not change or stop either medicine without medical advice.
| Sildenafil dose with doxazosin | Additional supine BP reduction | Additional standing BP reduction |
|---|---|---|
| 25mg | 7/7 mmHg | 6/6 mmHg |
| 50mg | 9/5 mmHg | 11/4 mmHg |
| 100mg | 8/4 mmHg | 4/5 mmHg |
These are averages, and infrequent reports of symptomatic postural hypotension occurred one to four hours after dosing. This combination is not forbidden, but it is one where a prescriber will want you stable on the alpha-blocker first and may choose a different starting strength. That is their decision to make with your full medicine list in front of them, not something to work out yourself.
Calcium channel blockers, ACE inhibitors, ARBs, beta blockers and diuretics
These are commonly prescribed medicines for high blood pressure, and they can often be used with sildenafil following an appropriate clinical assessment. They do not appear to cause a clinically significant change in how sildenafil is absorbed or cleared from the body. However, because both treatments can lower blood pressure, taking them together may result in an additional reduction in blood pressure.
For example, in a study of patients with hypertension who were already taking amlodipine 5mg or 10mg, adding sildenafil 100mg resulted in a mean additional reduction in supine blood pressure of 8 mmHg systolic and 7 mmHg diastolic.
This does not mean the combination is suitable for everyone. Your prescriber will consider your blood pressure, cardiovascular health, other medicines and how you respond to treatment before deciding whether sildenafil is appropriate.
It is also worth mentioning beta blockers because some people taking them are concerned about erectile dysfunction. Erectile difficulties can have several possible causes, including underlying health conditions and medicines. If you think a blood pressure medicine may be affecting your sexual function, speak with your prescriber rather than stopping it yourself.
| Medicine class | Status | What to expect |
|---|---|---|
| Nitrates, nicorandil, riociguat, poppers | Contraindicated | Absolute bar. No safe combination at any dose or interval |
| Alpha-blockers (doxazosin, tamsulosin, alfuzosin) | Caution | Additive fall in blood pressure and a risk of postural dizziness. Prescriber will assess timing and strength |
| Calcium channel blockers (amlodipine) | Usually manageable | Mean additional reduction of about 8/7 mmHg in the labelled study |
| ACE inhibitors (ramipril, lisinopril) | Usually manageable | Modest additive blood pressure reduction |
| ARBs (valsartan, losartan, candesartan) | Usually manageable | Modest additive blood pressure reduction, monitored rather than avoided |
| Beta-blockers (bisoprolol, atenolol) | Usually manageable | No pharmacokinetic interaction; additive effect generally modest, though some older beta-blockers may worsen erectile dysfunction by decreasing blood flow |
| Diuretics (bendroflumethiazide, indapamide) | Usually manageable | Additive effect; dehydration can amplify a fall in blood pressure |
Can I take Viagra with valsartan?
Valsartan is an angiotensin II receptor blocker (ARB) used to treat conditions including high blood pressure. It is not listed as a contraindicated combination with sildenafil. However, both medicines can lower blood pressure, so taking them together may increase the blood pressure lowering effect in some people.
There is no specific interaction study between valsartan and sildenafil in the sildenafil product information. Interaction references may classify the combination as requiring caution or monitoring because of the potential for an additive effect on blood pressure.
Your prescriber may consider your recent blood pressure readings, cardiovascular health, other medicines and whether you experience dizziness or light headedness when standing before deciding whether sildenafil is appropriate.
The same principle applies to other ARBs, such as losartan, candesartan and irbesartan. Do not stop or change your valsartan to take an erectile dysfunction medicine. Speak with your prescriber if you have concerns about the combination.
Warning Signs and What to Do
Most reported side effects of sildenafil are mild and temporary. Headache, flushing, nasal congestion and indigestion are among the commonly reported effects. Sildenafil can also cause a small reduction in blood pressure in some people.
Some symptoms need more urgent attention:
- Chest pain during or after sexual activity: Do not use a GTN spray or other nitrate medicine after taking sildenafil. Call 999 and tell the emergency team that you have taken sildenafil and when you took it. If you have a heart condition, make sure you understand this before starting treatment.
- Fainting or severe dizziness: Sit or lie down to avoid falling and seek medical advice. Severe or persistent symptoms should be assessed promptly by a healthcare professional.
- Sudden changes in vision or hearing: Stop taking sildenafil and seek urgent medical attention if you experience sudden vision loss or a sudden change or loss of hearing.
- An erection lasting more than four hours: Seek urgent medical attention. This is a medical emergency and should not be left to resolve on its own.
The warning about nitrates is particularly important for anyone who carries GTN for angina. If you have taken sildenafil and then develop chest pain, tell the emergency team that you have taken sildenafil. Do not use nitrate medicine unless a healthcare professional specifically advises you to do so in an emergency setting.
Why Erectile Dysfunction and High Blood Pressure Occur Together
Erections depend on healthy blood vessels, so conditions that affect blood vessel function can also affect erectile function. Long term high blood pressure can damage the endothelium, the inner lining of blood vessels involved in the production of nitric oxide. This can affect the blood flow needed to achieve and maintain an erection.
High blood pressure is also one of several factors associated with erectile dysfunction. Because the blood vessels supplying the penis are relatively small, changes in vascular health may sometimes become noticeable through erectile difficulties before other symptoms of cardiovascular disease appear.
This is one reason persistent or new erectile dysfunction is worth discussing with a healthcare professional rather than treating it as an isolated problem. A blood pressure check and an assessment of cardiovascular risk may be appropriate.
Some medicines used to treat high blood pressure may also contribute to erectile difficulties in some people. Thiazide diuretics and some older beta blockers have been associated with erectile dysfunction. If your symptoms started after beginning or changing a blood pressure medicine, discuss this with your prescriber. They can review your treatment and decide whether an alternative may be appropriate.
Do not stop taking prescribed blood pressure medicine without medical advice.
Getting Assessed, and What Treatment Costs
Sildenafil is a prescription only medicine in the UK, so an appropriate clinical assessment is needed before it is supplied. This is particularly important if you have high blood pressure, heart disease or take medicines that affect blood pressure.
During an assessment, provide a complete list of the medicines and supplements you take. This should include medicines you use only occasionally, such as GTN spray, medicines bought without a prescription, herbal products and recreational substances. Recreational nitrites known as poppers are particularly important to mention because they must not be used with sildenafil.
An online consultation may be completed at home and reviewed by a UK registered prescriber. If treatment is considered appropriate, it can be dispensed by a GPhC registered pharmacy.
If your medical history is more complex, the appropriate next step may be further assessment by your GP, cardiology team or another healthcare professional rather than an immediate prescription. This is a normal part of making sure treatment is suitable for you.
Prices may vary according to the strength and quantity prescribed. The price confirmed at consultation is the price that applies.
Changing from one PDE5 inhibitor to another does not remove the nitrate interaction. PDE5 inhibitors have the same important contraindication with nitrate medicines, so switching treatment is not a way around this particular safety issue.
Medical Disclaimer
This article provides general information and does not constitute medical advice. It does not replace guidance from a qualified healthcare professional or the patient information leaflet supplied with your medicine.
Sildenafil is a prescription only medicine and should only be used following an appropriate clinical assessment. Treatment suitability and strength depend on individual factors, including your medical history, cardiovascular health and other medicines.
Sildenafil is not licensed to treat systemic high blood pressure and should never be used instead of prescribed antihypertensive medicine. Do not stop or change any prescribed medicine without speaking with your prescriber.
Sildenafil must not be taken with nitrate medicines, nicorandil, riociguat or recreational nitrites known as poppers because of the risk of a significant fall in blood pressure.
Call 999 if you develop chest pain after taking sildenafil and tell the emergency team that you have taken it. Seek urgent medical attention for fainting, sudden vision or hearing changes, or an erection lasting more than four hours.
