Can You Take Alka-Seltzer After Taking Nitroglycerin?
In our latest question and answer, our pharmacist discusses the safety of combining nitroglycerin and Alka-Seltzer.
Can I take an Alka-Seltzer after taking a nitrogen pill?
Jan 19, 2023- Some Alka-Seltzer products contain aspirin, which can interact with nitroglycerin and potentially increase side effects like low blood pressure.
- Taking Alka-Seltzer after nitroglycerin appears to be safer than taking it before, based on available studies.
- Check your Alka-Seltzer product label to see if it contains aspirin, and talk to your doctor or pharmacist before using both medications together.
Answer
Thanks so much for reaching out! Your question isn't entirely clear in regard to what 'nitrogen pill' you are referring to, but I'm going to assume you are talking about nitroglycerin. If this is incorrect, please write back and let us know.
Regarding nitroglycerin, which is used to relieve chest pain, it does interact with some Alka-Seltzer products.
It is important to note here that Alka-Seltzer is a brand name, and there are several different products that use the name. I'm not sure which Alka-Seltzer product you are referring to, but there is an interaction specifically with Alka-Seltzer products that contain aspirin. Here is one example of an Alka-Seltzer product that contains aspirin:

Interaction Details
The interaction here is that aspirin (which is contained in some Alka-Seltzer products) may increase the concentrations of nitroglycerin, potentially increasing the risk of side effects, such as hypotension (i.e., low blood pressure) and increased heart rate. One study concluded the following:
We conclude that pretreatment with 1 g of aspirin increases NTG [nitroglycerin] plasma levels and therefore significantly enhances the pharmacodynamic effects of NTG.
Now, it is important to note a few things.
For one, most studies show that only high doses of aspirin (over 1 gram) are likely to cause an interaction. Alka Seltzer tablets in the product I pictured above contain only 325mg (per tablet). Additionally, not all studies have found that aspirin significantly affects nitroglycerin concentrations.
Lastly, in your question, you wanted to know about taking Alka-Seltzer after nitroglycerin, and that appears to be safe. Documented interactions have occurred when aspirin is given before nitroglycerin.
So, overall, this interaction is thought to be a relatively minor one and probably not very likely to be of significance for most people. Nevertheless, I would be cautious of using both together.
Final Words
I hope you found this helpful!
Remember that the interaction is between Alka-Seltzer products that contain aspirin. Other Alka-Seltzer products that don't aren't known to interact with nitroglycerin.
References & sources
Glossary — Terms in This Answer
- Nitroglycerin
- A medication used to relieve chest pain by widening blood vessels and improving blood flow to the heart.
- Aspirin
- A common pain reliever and anti-inflammatory medication that can also help prevent blood clots.
- Hypotension
- Abnormally low blood pressure, which can cause dizziness or lightheadedness.
- Interaction
- A situation where two medications affect each other's actions or increase the risk of side effects.
- Pharmacodynamic effects
- The way a drug acts on the body and produces its intended biological response.
- Plasma levels
- The concentration of a drug in the liquid part of the blood.
- Concentrations
- The amount of a substance present in a given volume, such as medication in the bloodstream.
- Side effects
- Unwanted or harmful reactions that occur in addition to the intended effect of a medication.