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Viagra, also known as sildenafil, is a widely prescribed medication for erectile dysfunction (ED) in adults. While it is a popular and effective treatment option, it is essential to be aware of potential drug interactions and contraindications.
In this article, we will discuss the drugs and substances that should not be taken with Viagra, the reasons behind these interactions, and the precautions to take.
Related: How does Viagra work
Viagra may not be suitable for everyone, and certain medications or health conditions can increase the risk of harmful interactions or contraindications. Before starting Viagra, discuss your medical history, current medications, and overall health with your doctor to determine if Viagra is a safe and appropriate treatment option.
Viagra is contraindicated for use with nitrate medications due to the increased risk of life-threatening hypotension (low blood pressure). Nitrate medications are often prescribed for the treatment of angina pectoris (chest pain) and include drugs such as nitroglycerin (Nitrostat, NitroMist) and isosorbide dinitrate (Isordil).
When taken together, combining Viagra and nitrates can cause blood pressure to drop to dangerously low levels. For this reason, medical professionals will not prescribe nitrate medications and Viagra together.
Patients taking nitrates should also be informed of the potential risks of using Viagra within 24 hours after taking nitrate medication.
If you are taking nitrates, it is essential to inform your healthcare provider before starting Viagra. They may be able to recommend alternative treatments for your ED that do not pose a risk when taken with nitrates. Additionally, if you are taking Viagra and experience chest pain, do not use nitrates for relief; instead, seek immediate medical attention.
Another class of medications that can interact with Viagra is guanylate cyclase (GC) stimulators, such as riociguat (Adempas). Like nitrates, GC stimulators can cause a dangerous drop in blood pressure when taken with Viagra. As a result, healthcare professionals will not prescribe GC stimulators and Viagra together.
If you take a GC stimulator medication, inform your healthcare provider before starting Viagra. They can discuss alternative treatment options for your ED that do not pose a risk when taken with GC stimulators.
Viagra can interact with certain blood pressure medications, such as alpha-blockers and other antihypertensive agents. These interactions can increase the risk of sildenafil-induced hypotension (low blood pressure). Some examples of alpha-blockers include doxazosin (Cardura), terazosin (Hytrin), and tamsulosin (Flomax).
If you take blood pressure medications, inform your healthcare provider before starting Viagra. They may need to adjust your Viagra dosage or recommend alternative treatments for your ED. Additionally, they may advise you to monitor your blood pressure and pulse while taking Viagra, especially when starting the medication or adjusting the dosage.
The CYP3A4 enzyme primarily metabolizes Viagra, and certain medications known as CYP3A4 inhibitors can increase the plasma concentrations of sildenafil, leading to an increased risk of side effects. Some examples of CYP3A4 inhibitors include:
If you take a CYP3A4 inhibitor, your healthcare provider may recommend starting with a lower initial dose of Viagra (25 mg) to minimize the risk of side effects. They may also advise you to monitor for potential side effects, such as headaches, flushing, and dizziness.
Grapefruit and grapefruit products like grapefruit juice can interact with Viagra. This interaction can increase the levels of Viagra in your body, leading to an increased risk of side effects.
You should avoid consuming grapefruit and grapefruit products while taking Viagra. If you regularly consume grapefruit and wish to continue, your healthcare provider may adjust your dosage of Viagra accordingly.
Alcohol can potentially interact with Viagra, although the risk may depend on the amount of alcohol consumed. Viagra and alcohol can lower blood pressure, so taking the two together can cause blood pressure to drop to dangerously low levels.
If you drink alcohol, inform your healthcare provider before starting Viagra. They can discuss with you how much alcohol, if any, is safe to drink while taking the medication.
Related: How long does Viagra stay in your system
Cannabis (marijuana) and cannabis products, such as cannabidiol (CBD), can interact with Viagra. Tetrahydrocannabinol (THC), a component of cannabis, may increase Viagra levels in the body, which could increase the risk of side effects, such as low blood pressure.
Before starting Viagra, inform your healthcare provider if you use cannabis or CBD products. By sharing this information, you can help prevent potential interactions. Note that cannabis is illegal at the federal level in the United States but is legal in many states to varying degrees.
St. John’s Wort, an herbal supplement commonly used to treat depression, can interact with Viagra. Taking St. John’s Wort may make Viagra less effective.
If you are taking St. John’s Wort, inform your healthcare provider before starting Viagra. They may adjust your Viagra dosage or recommend that you stop using St. John’s Wort to avoid potential interactions.
Patients with liver or severe kidney problems may have increased levels of Viagra in their bodies, leading to an increased risk of side effects. This is because these conditions can affect the metabolism and clearance of sildenafil.
If you have liver or severe kidney problems, your healthcare provider may recommend a lower initial dose of Viagra (25 mg) to minimize the risk of side effects. They may also closely monitor your response to the medication and adjust your dosage as needed.
Certain health conditions may increase the risk of interactions with Viagra, such as:
Before starting Viagra, inform your healthcare provider about your health history and any existing medical conditions. They can help determine whether Viagra is safe for you and may recommend alternative treatments.
Viagra is an effective treatment for erectile dysfunction, but it is essential to be aware of potential interactions and contraindications. Discussing your medical history and current medications with your healthcare provider can help ensure you use Viagra safely and effectively.
Always inform your healthcare provider of any new medications or supplements you start taking while on Viagra to avoid potential interactions and follow their recommendations for proper use and monitoring.
If you have any concerns or questions about Viagra and its possible interactions, consult your healthcare provider for personalized advice and recommendations.
