Viagra, known generically as sildenafil, is what many men use to treat erectile dysfunction (ED). While effective, it’s crucial to understand that Viagra can interact with a variety of other medications, potentially leading to harmful effects. These interactions can change how Viagra works, reduce its effectiveness, or increase the risk of side effects, some of which can be serious.
To ensure your safety and the effectiveness of Viagra, it’s vital to be aware of potential drug interactions. This article will delve into what Viagra interacts with, providing a comprehensive overview to help you make informed decisions about your health.
Viagra and Other Erectile Dysfunction Medications
Combining Viagra with other erectile dysfunction (ED) medications is strongly discouraged. This includes both prescription drugs and over-the-counter or natural remedies. The reason is simple: doubling up on ED medications significantly increases the risk of adverse side effects.
Examples of ED medications you should not take with Viagra include:
- Tadalafil (Cialis)
- Avanafil (Stendra)
- Vardenafil
- Alprostadil (Muse, Caverject, Caverject Impulse, Edex)
- Herbal remedies like l-arginine and yohimbine
Taking Viagra with these medications can dramatically increase your risk of:
- Hypotension (Low Blood Pressure): ED medications work by relaxing blood vessels to improve blood flow. Combining them can lead to excessively low blood pressure.
- Priapism: This is a prolonged, painful erection lasting four hours or more and is a medical emergency requiring immediate treatment.
If you are considering Viagra for ED, it’s essential to discuss all other ED treatments you are using or considering with your doctor. They can advise on the safest and most effective approach for you.
Viagra and Nitrates: A Dangerous Combination
One of the most critical Viagra interactions to be aware of is with nitrate medications. Nitrates are commonly used to treat angina, a type of chest pain caused by reduced blood flow to the heart. This combination is extremely dangerous and can have life-threatening consequences.
Nitrates, like Viagra, affect blood vessels. When taken together, they can cause a drastic and sudden drop in blood pressure, leading to serious cardiovascular events.
Examples of nitrates to avoid when taking Viagra include:
- Nitroglycerin (Nitromist, Nitro-Dur, Nitrolingual Pumpspray, Gonitro, others)
- Isosorbide mononitrate (Monoket)
- Isosorbide dinitrate (Dilatrate SR, Isordil)
- Glyceryl trinitrate
- Amyl nitrate (poppers)
- Alkyl nitrate (poppers)
- Butyl nitrate (poppers)
The interaction between Viagra and nitrates can result in:
- Severe Hypotension: Dangerously low blood pressure that can cause dizziness, fainting, and even shock.
- Heart Attack and Stroke: The sudden drop in blood pressure can strain the heart and increase the risk of these critical events.
Never take Viagra if you are using any nitrate medication. If you experience chest pain, inform your doctor about Viagra use before they administer any nitrates.
Viagra and Pulmonary Arterial Hypertension (PAH) Drugs
Viagra itself is a type of medication called a PDE5 inhibitor. Other PDE5 inhibitors are used to treat pulmonary arterial hypertension (PAH), a condition involving high blood pressure in the arteries of the lungs. Combining Viagra with these PAH drugs can also lead to dangerously low blood pressure.
Examples of PAH medications that should not be taken with Viagra include:
- Riociguat (Adempas)
- Sildenafil (Revatio – note that Revatio is also sildenafil, just a different brand and dosage for PAH)
- Tadalafil (Adcirca – again, tadalafil, like Cialis, but Adcirca is for PAH)
Using Viagra with these medications can cause:
- Excessive Blood Pressure Lowering: The combined effect of PDE5 inhibitors can lead to blood pressure dropping too low.
It’s crucial to inform your doctor if you are taking any medications for PAH before starting Viagra.
Viagra and Blood Pressure Medications
Viagra can cause a temporary decrease in blood pressure. Therefore, when taken with other blood pressure-lowering medications, the effect can be amplified, potentially leading to hypotension.
Types of blood pressure medications that can interact with Viagra include:
- ACE inhibitors
- Angiotensin II receptor blockers (ARBs)
- Beta-blockers
- Calcium channel blockers
- Diuretics (water pills)
While it may be possible to take Viagra with blood pressure medications, it’s essential to do so under medical supervision. Your doctor may need to adjust the dosage of Viagra or your blood pressure medication to minimize the risk of hypotension. They often start with a lower 25mg dose of Viagra for patients on blood pressure medications.
Alpha-blockers and Viagra:
A specific type of blood pressure medication, alpha-blockers, warrants particular attention. Alpha-blockers are also used to treat benign prostatic hyperplasia (BPH), or enlarged prostate. The combination of Viagra and alpha-blockers can significantly increase the risk of low blood pressure, leading to dizziness, lightheadedness, and fainting.
Examples of alpha-blockers include:
- Alfuzosin (Uroxatral)
- Doxazosin (Cardura)
- Prazosin (Minipress)
- Tamsulosin (Flomax)
- Terazosin
If you are taking an alpha-blocker, your doctor will likely start you on a lower 25mg dose of Viagra to minimize the risk of hypotension. It’s important to report any dizziness, lightheadedness, or fainting to your doctor after taking Viagra in combination with an alpha-blocker.
Viagra and Illegal Drugs
The use of Viagra with “poppers,” illegal drugs containing nitrates such as amyl nitrate, alkyl nitrate, and butyl nitrate, is strictly contraindicated due to the risk of a dangerous drop in blood pressure, potentially leading to heart attack or stroke, as previously discussed.
Beyond poppers, the safety of combining Viagra with other illegal drugs is largely unknown. However, it’s reasonable to assume that some illegal substances could also pose risks when taken with Viagra, particularly those that affect the cardiovascular system.
Examples of illegal drugs that might interact negatively with Viagra include:
- Cocaine
- Amphetamines
- MDMA (Ecstasy, Molly)
If you are considering using illegal drugs with Viagra, it’s crucial to understand the potential risks and discuss them with your doctor. However, it is generally advisable to avoid combining Viagra with any recreational drugs due to unpredictable and potentially dangerous interactions.
Viagra and Certain BPH Drugs
As mentioned earlier, alpha-blockers are used to treat both high blood pressure and benign prostatic hyperplasia (BPH). Therefore, the same interaction risks apply when combining Viagra with alpha-blockers used for BPH. Taking Viagra with these medications can lead to an increased risk of low blood pressure, dizziness, lightheadedness, and fainting.
Examples of alpha-blockers used for BPH that can interact with Viagra include the same list as above:
- Alfuzosin (Uroxatral)
- Doxazosin (Cardura)
- Prazosin (Minipress)
- Tamsulosin (Flomax)
- Terazosin
If you are taking an alpha-blocker for BPH, your doctor will recommend a lower starting dose of Viagra and monitor you for any signs of low blood pressure.
Viagra and Adderall & Xanax
While Viagra hasn’t been specifically tested with Adderall (amphetamine salts) or Xanax (alprazolam, a benzodiazepine), potential interactions are possible.
Viagra and Adderall: Adderall is a stimulant that can increase heart rate and blood pressure. Viagra can lower blood pressure. While their effects on blood pressure might seem opposite, the combination could still strain the cardiovascular system or lead to unpredictable blood pressure fluctuations. It’s best to consult your doctor before combining these.
Viagra and Xanax: Xanax can sometimes lower blood pressure, cause dizziness, and fainting. Viagra can also lower blood pressure. Combining them could increase the risk of these side effects and potentially lead to dangerous hypotension. Medical advice is recommended before taking these together.
Viagra and Antidepressants
Generally, it is considered safe to take Viagra with antidepressants. In fact, Viagra is sometimes prescribed to treat erectile dysfunction that is a side effect of certain antidepressants, particularly selective serotonin reuptake inhibitors (SSRIs) like sertraline (Zoloft).
However, it’s always best to discuss this combination with your doctor to ensure there are no specific concerns based on the particular antidepressant you are taking.
Viagra and Certain Antimicrobials
Certain antimicrobial medications, used to treat infections, can affect how Viagra is metabolized (broken down) in the body. These antimicrobials can slow down the breakdown of Viagra, causing it to build up in your system. This increased level of Viagra can raise your risk of side effects.
Examples of antimicrobials that can interact with Viagra include:
- Erythromycin
- Clarithromycin
- Cimetidine
- Ritonavir and other protease inhibitors (used for HIV)
- Ketoconazole and itraconazole (antifungal medications)
If you are prescribed any of these antimicrobials, your doctor will likely recommend a lower starting dose of Viagra (25mg). If you are taking ritonavir, you should not take more than one 25mg dose of Viagra within a 48-hour period.
Viagra and Herbs, Supplements, and Foods
Currently, there are no widely reported herb or supplement interactions with Viagra. However, it’s still prudent to consult your doctor or pharmacist before combining Viagra with any herbal or dietary supplements to ensure safety.
Regarding food, no specific food interactions with Viagra have been officially reported.
Viagra and Grapefruit:
Grapefruit and grapefruit juice can interact with several medications by affecting liver enzymes that break down drugs. While the evidence for a significant interaction between grapefruit and Viagra is limited, some studies suggest that grapefruit juice might slightly increase Viagra levels in the blood. This could potentially increase the risk of side effects like headaches, flushing, or dizziness, although this hasn’t been definitively proven in studies.
If you consume grapefruit or grapefruit juice regularly, discuss this with your doctor while taking Viagra. They can advise if it’s safe for you or if you should limit or avoid grapefruit consumption.
Consulting Your Doctor is Key
This article provides a comprehensive overview of potential Viagra interactions. However, it is not exhaustive, and individual responses to medications can vary.
Before taking Viagra, it is crucial to:
- Provide your doctor with a complete list of all medications you are taking, including prescription drugs, over-the-counter medications, vitamins, herbs, and supplements.
- Discuss any pre-existing health conditions you have, especially heart conditions, blood pressure issues, or prostate problems.
- Ask your doctor any questions you have about Viagra and potential interactions.
Your doctor can assess your individual risk factors and provide personalized guidance on whether Viagra is safe for you and how to minimize the risk of interactions. Never start, stop, or change the dosage of any medication, including Viagra, without consulting your healthcare provider first. Self-treating can be dangerous, and professional medical advice is essential for safe and effective Viagra use.
