Sildenafil (brand name: Viagra) is one drug that people have been inquiring about not only because it is a medication for erectile dysfunction. Men with heart conditions and those who use nitrates have asked if it is safe to use both of these substances together.
It is important to stress from the start that sildenafil and nitroglycerin do not mix (1). Heeding this warning will keep you safe. That is one bit of information that will be worth sharing.
Warnings and Contraindications
The FDA (US Food and Drug Administration) has provided sufficient warnings to the public that products containing nitrates shouldn’t be consumed together with impotence drugs such as sildenafil. This same warning was also issued by Pfizer, the manufacturer of Viagra.
What is the reason for the said warning?
The reason behind the contraindication and the subsequent warning is the fact that both of these medications can cause a drastic drop in blood pressure (2). If you have blood pressure issues or if you are suffering from angina pectoris, then taking these drugs at the same time is not advisable.
Understanding How Nitrates and Sildenafil Work
So, how do these two medications work? Answering this question will clear up the details for everyone. Note that both nitroglycerin and sildenafil affect the muscles that control the size of the blood vessels (3).
When these muscles relax, the diameter of the blood vessels then tends to get bigger. This results in an increase in blood flow to specific parts of the body. In the case of sildenafil, the groin and penis area gets more blood.
However, it also has another effect. Apart from increasing blood flow to the nether regions of the body, blood pressure gets reduced. Some people think that blood pressure reduction is a good thing.
Well, it is great for people who have high blood pressure. However, this increased reduction in blood pressure may be detrimental for people with angina or similar health conditions.
Those with angina will feel the reduction of blood pressure going to the heart. It will then manifest specific key symptoms like dizziness. If left untreated, this condition may even lead to a heart attack.
Since 1998 there have been a total of 130 deaths related to the intake of sildenafil or Viagra. Of the 130 men in question, 16 of them died while taking sildenafil with a type of nitrate.
That is why the authorities have prohibited the intake of nitrates with sildenafil together (4). Remember that nitroglycerin is not the only nitrate.
The following is a list of nitrates:
- Erythritol Tetranitrate
- Nitrol ointment
- Pentaerythritol tetranitrate
- Sodium nitroprusside
Note that the list above is only a partial list of nitrates (5). Identifying nitrates will not be that easy. There are 20 prescription forms of this drug, and remembering the rest will be very difficult.
The best practice here is to consult with your doctor first before taking any type of medication or drug with sildenafil, Viagra, or another male enhancement formula.
The Case of Grapefruits and Herbal Tonics
Even if it is only an herbal tonic as long as it is for male or sexual enhancement, then you should check with your doctor first. Even herbal tonics may contain possible nitrates or ingredients that may enhance the effects of sildenafil.
For instance, concentrated grapefruit juice can enhance the effects or levels of sildenafil in the body (6). You also get the same results by eating a lot of grapefruit.
Note that grapefruit juice or extracts can also delay the effects of other forms of medication to work in the body. Remember, as a rule of thumb, don’t drink grapefruit juice and take Viagra or sildenafil.
It would be impractical to make a list of the number of drugs that could interact with nitrates. It would just make this guide too long. Note that there are more than 201 drugs and other medications that can interact with nitroglycerin (7).
However, do take note of the following figures:
- There are only eight major possible interactions
- It can also make minor interactions with 28 other drugs and substances
- There are a total of 165 possible moderate interactions
Expect interactions when taking nitroglycerin with Cialis (tadalafil), Viagra (sildenafil), and Xanax. When your doctor tells you that a drug has a major interaction with nitroglycerin (e.g., with sildenafil), it means that the medical risk is highly significant.
That also means that the risk of the interactions of these drugs is so high that it outweighs any potential benefits. When the level of possible interaction between two medications is moderate, then you should use them only upon a doctor’s advice.
Your doctor will prescribe them only under particular circumstances. However, if tests indicate and your doctor’s opinion is that the interaction is only mildly significant, then the risk is minimal.
However, you should still let your doctor know that you intend to take nitroglycerin with a drug with a minor associated interaction. Your doctor will always monitor your condition and will assess any possible risks.
But What If You Have to Take Nitroglycerin?
Some people have to take nitroglycerin or other nitrates from time to time as part of a medical regimen. In such cases, again, you should seek advice from a qualified medical professional.
Your doctor will usually advise you not to take sildenafil within 24 hours after you have taken your dose of nitroglycerin. If you take sildenafil too early, then it may cause hypotension and will manifest any of the following symptoms:
- Lowered blood pressure
Your doctor will also give you the same advice if an over the counter flu, cough, and other medication, heart medication, or hypertension medication may interact with sildenafil.
Note that nitroglycerin is not free of side-effects (8). Some of the known side-effects of this drug include:
- Lowered blood pressure
- Arrhythmia (irregular heartbeat)
Add to that the possible side-effects and general effects of sildenafil to the body, then you may find possible complications. Remember that as a general rule, you should never take both of these drugs at the same time.
Consult with your doctor if you have to take them. Follow best practices to keep yourself safe.