What is Milk of Magnesia?
Milk of Magnesia is a medication used as a laxative to treat occasional constipation. The active ingredient is magnesium hydroxide, which works by drawing water into the intestines to help soften and relax the stool, allowing it to pass more easily.
Some key facts about Milk of Magnesia:
- It typically comes in liquid or chewable tablet form.
- The adult dosage is 2-4 tablespoons or 2-4 chewable tablets taken orally.
- It generally begins working in 30 minutes to 6 hours to produce a bowel movement.
- Common side effects may include diarrhea, upset stomach, or nausea.
Milk of Magnesia has been around since the early 1900s and is available as an over-the-counter medication. The liquid form tends to be the most commonly used. It has a chalky taste and thick, milky-white consistency. It is considered safe for most people when used occasionally, but should not be used long-term without medical supervision.
How Long Does Unopened Milk of Magnesia Last?
If stored properly, unopened Milk of Magnesia has a relatively long shelf life. Here is how long it lasts:
- Liquid form: 2 to 3 years past the expiration date printed on the bottle.
- Chewable tablet form: Up to 1 year past the expiration date if stored in a cool, dry place.
The expiration date listed on the package is typically quite conservative to ensure effectiveness and safety. As long as the bottle seal remains intact on liquid preparations or the tablets show no change in color or texture, Milk of Magnesia lasts significantly longer than the labeled expiration date.
However, it’s always best practice to buy a new bottle if your Milk of Magnesia is expired, as very prolonged storage can increase risk of decreased potency.
Tips for Proper Storage
To get the most shelf life out of Milk of Magnesia:
- Store at room temperature away from excess heat and moisture.
- Keep the bottle tightly sealed when not in use.
- Don’t store in humid environments like the bathroom medicine cabinet.
- Avoid freezing temperatures which can degrade the medication.
With proper storage, an unopened bottle of Milk of Magnesia liquid or a sealed container of chewable tablets can safely be used for several years past the printed expiration date. However, it’s best to always check for changes in appearance, texture, or smell before taking expired Milk of Magnesia.
How Long Does Opened Milk of Magnesia Last?
Once opened, Milk of Magnesia has a shorter shelf life and needs to be discarded sooner:
- Liquid Milk of Magnesia lasts 6 to 12 months.
- Chewable tablets last 3 to 6 months.
Exposure to air degrades the active ingredients over time. Liquid preparations also run the risk of bacterial contamination once the protective seal is broken. This makes it unsafe to take Milk of Magnesia much beyond 6 to 12 months after opening.
Maximizing Opened Shelf Life
To maximize the shelf life of opened Milk of Magnesia:
- Store the bottles or containers at room temperature away from excess heat and moisture.
- Keep the bottles tightly sealed when not in use.
- Don’t store Milk of Magnesia in humid environments like bathrooms.
- Keep away from direct sunlight, which can degrade medications over time.
- Check regularly for changes in smell, appearance, or texture.
Discard any Milk of Magnesia that shows discoloration, clumping, evidence of moisture, or other physical changes. An opened bottle should also be discarded after 1 year even if no changes are observed.
For optimal safety and effectiveness, buy a new bottle of Milk of Magnesia after using one up within 6 to 12 months of opening. Never take expired liquid preparations or tablets that have surpassed their opened shelf life.
How to Tell if Milk of Magnesia Has Expired
Here are some signs that your Milk of Magnesia may be expired and time to discard:
Liquid Form
- Cloudy appearance instead of opaque white liquid
- Separation, clumping, or sediment at the bottom
- An odor or strange smell when opened
- Bottle cap is loose or leaking
- Liquid is difficult to pour or clumps together
Chewable Tablets
- Tablets are discolored instead of plain white
- Visible moisture inside the container
- Tablets don’t have a smooth texture
- Chalky smell or taste
- Container seal is loose or tablets exposed to air
Always inspect Milk of Magnesia carefully before use. If you notice any changes to the medication, it is safest to purchase a new sealed bottle or container. Taking expired or degraded Milk of Magnesia can potentially lead to decreased effectiveness or stomach upset.
Does Expired Milk of Magnesia Go Bad?
Milk of Magnesia does not necessarily go “bad” in the sense of causing illness or spoiling. However, degraded or expired Milk of Magnesia can become less effective or stop working.
Here’s what happens when Milk of Magnesia expires:
- The active ingredient, magnesium hydroxide, starts to break down.
- Potency and effectiveness at relieving constipation decreases.
- The liquid can start to separate or develop more chalky sediment.
- Tablets can become brittle, discolored, or develop a stale taste and smell.
While toxic mold growth is unlikely, contamination in liquid Milk of Magnesia is possible in very old bottles that have been opened. This can lead to increased risk of stomach upset or diarrhea.
So while expired Milk of Magnesia won’t make you sick from foodborne toxins, taking degraded medication can potentially lead to complications or lack of effectiveness. It is not worth taking the chance with outdated or questionable Milk of Magnesia.
Is it Safe to Take Expired Milk of Magnesia?
It is generally not recommended to take expired Milk of Magnesia. As the active ingredients degrade over time, you run the risk of the medication not working as intended.
Potential risks of taking expired Milk of Magnesia include:
- No relief of constipation symptoms
- Unpleasant side effects like stomach cramps or diarrhea
- Interactions with other medications you are taking
- Intestinal blockages for some medical conditions
Liquid Milk of Magnesia that is very old or has been contaminated also poses risks of bacterial infection. Unless it is an absolute emergency, it is better to avoid using expired Milk of Magnesia.
The shelf lives given for unopened and opened Milk of Magnesia account for degradation of the active ingredients over time. While the medication may still provide some level of effectiveness shortly past its expiration date, this diminishes the longer it is stored after opening or expiring.
For reliable relief of occasional constipation, stick to Milk of Magnesia within its expiration date and discard opened bottles after 6 to 12 months. Never take the medication if you notice any changes in appearance, consistency, or smell. Expired Milk of Magnesia should always be replaced with a fresh, sealed bottle.
FAQs
Can expired Milk of Magnesia make you sick?
Expired Milk of Magnesia is unlikely to directly cause illness or toxicity on its own. However, taking degraded medication can potentially lead to diminished effectiveness, intestinal issues, or interactions with other medications you take.
How long does liquid Milk of Magnesia last once opened?
An opened bottle of liquid Milk of Magnesia typically lasts 6 to 12 months. Always store it properly sealed and away from heat and humidity to get the longest opened shelf life.
Is it bad to use Milk of Magnesia after the expiration date?
It is generally not recommended. While not directly harmful, the potency and effectiveness of expired Milk of Magnesia drops over time. This means it may not provide the desired laxative results.
Can you take Milk of Magnesia years after expiration?
No, you should not take Milk of Magnesia even 1 year after the expiration date. The medication degrades and is not reliably effective or safe after its shelf life. Always discard and replace expired bottles.
How do you dispose of expired Milk of Magnesia?
To safely dispose of expired Milk of Magnesia, mix it with an unpalatable substance like dirt, cat litter, or coffee grounds in a sealed plastic bag. This helps prevent unintended ingestion. Then throw the bag in your regular household trash.
The Bottom Line
Milk of Magnesia typically lasts up to 2-3 years past its printed expiration date if unopened, and 6-12 months once opened. Look for changes in appearance, smell, or texture to check for degradation. Expired or long-stored Milk of Magnesia may not provide effective relief of constipation symptoms. It’s always best to replace your Milk of Magnesia with a new sealed bottle once expired for optimal safety and effects.