A basic saline solution requires just two ingredients: non-iodized salt and sterilized water, mixed to a 0.9% concentration. That translates to roughly half a teaspoon of salt per cup of water. The process takes about 20 minutes, most of which is just waiting for water to boil and cool.
What You Need
Gather these before you start:
- Non-iodized salt. Pickling salt or canning salt works best. Avoid table salt, which contains iodine and anti-caking agents that can irritate nasal passages and skin. The American Academy of Allergy, Asthma & Immunology specifically recommends salt with no iodide, anti-caking agents, or preservatives.
- Baking soda (optional but recommended). Adding a small amount acts as a buffer, making the solution gentler on sensitive tissue. This is especially helpful for nasal rinses.
- Clean water. Tap water is not safe for nasal irrigation or wound care without boiling it first.
- A clean container. Glass jars work well. Wash the container with hot, soapy water and rinse thoroughly before use.
Why You Must Boil the Water
Tap water can harbor organisms that are harmless when swallowed but dangerous when introduced into nasal passages or open wounds. The CDC recommends bringing water to a rolling boil for 1 minute to make it safe. If you live at an elevation above 6,500 feet, boil for 3 minutes instead. Alternatively, you can use distilled water purchased from a store, which skips the boiling step entirely.
Step-by-Step Recipe
This recipe makes roughly one cup of saline, enough for a single nasal rinse or wound cleaning session.
Boil 8 ounces (1 cup) of water at a rolling boil for at least 1 minute, then remove from heat. While the water is still warm, stir in half a teaspoon of non-iodized salt until fully dissolved. If you’re making this for nasal rinsing, add a pinch of baking soda as well. Let the solution cool to lukewarm or room temperature before use. Water that’s too hot will burn delicate tissue.
For larger batches (useful if you rinse daily), the Cleveland Clinic recommends combining 3 teaspoons of non-iodized salt with 1 teaspoon of baking soda as a dry mix you can store in a sealed container. When you’re ready to use it, dissolve 1 teaspoon of that dry mix into 8 ounces of boiled or distilled water.
How to Store It Safely
Homemade saline has no preservatives, so bacteria begin growing in it relatively quickly. According to UC Davis Health, you should refrigerate any unused solution and discard it after three days. Making fresh batches is always preferable, especially for nasal irrigation or wound care. If you premix the dry ingredients (salt and baking soda), the powder keeps indefinitely in an airtight container, so you can quickly prepare a fresh solution each time.
Common Uses at Home
A 0.9% saline solution matches the salt concentration of your body’s own fluids, which is why it doesn’t sting or irritate healthy tissue. This makes it useful for several purposes.
For nasal rinsing, saline flushes out mucus, allergens, and irritants. You can use it with a neti pot, squeeze bottle, or bulb syringe. Tilt your head to one side over a sink, pour the solution into the upper nostril, and let it drain from the lower one. Breathe through your mouth during the process.
For wound cleaning, gently pour or squirt lukewarm saline over minor cuts, scrapes, or abrasions to wash away debris. It cleans without damaging new tissue the way hydrogen peroxide or rubbing alcohol can.
For gargling, a saline rinse can soothe a sore throat. Gargle for 15 to 30 seconds and spit it out.
What Homemade Saline Should Not Be Used For
Homemade saline is not sterile in the way commercially manufactured solutions are. It is not safe for contact lenses. Contact lens solutions contain specific disinfectants and buffering agents that homemade versions cannot replicate, and using anything else risks serious eye infections. Similarly, homemade saline should never be used for IV infusion or injection. Those applications require pharmaceutical-grade sterile saline prepared in controlled environments.
If you need saline for eye irrigation after getting debris or a chemical splash in your eye, a store-bought sterile saline or clean running water is a better choice than a homemade batch.
Getting the Concentration Right
The standard 0.9% concentration is called isotonic, meaning it matches your body’s natural salt level. Going significantly higher creates a hypertonic solution, which draws moisture out of tissue. Hypertonic saline (3% and above) is used in clinical settings for specific conditions like severe head injuries and certain respiratory problems, but those concentrations are not appropriate for home use. Sticking to the half-teaspoon-per-cup ratio keeps you in the isotonic range, which is gentle enough for daily use on nasal passages, skin, and throat tissue.
If your solution stings, you likely added too much salt. If it feels like plain water, you may not have added enough. A properly mixed batch should feel neutral, neither burning nor watery, when it contacts your nasal lining or an open cut.