Can You Take Expired Levothyroxine?
Levothyroxine is a synthetic version of the thyroid hormone thyroxine that is used to treat hypothyroidism. Hypothyroidism occurs when the thyroid gland does not produce enough thyroid hormones to meet the body’s needs. Levothyroxine replaces the thyroid hormone to restore normal levels.
Like most medications, levothyroxine has an expiration date on the packaging. This raises the question of whether it is safe or effective to take expired levothyroxine. There are a few factors to consider when determining if you can take expired levothyroxine.
How Levothyroxine Works
Levothyroxine contains the active ingredient levothyroxine sodium, which is identical to the thyroxine hormone produced naturally by the thyroid gland. It works by binding to thyroid hormone receptors in the body to restore normal thyroid hormone levels.
Thyroid hormones play an important role regulating metabolism, growth, development, and mood. When thyroid hormone levels are low, the body’s processes slow down, leading to symptoms of hypothyroidism like fatigue, weight gain, dry skin, and depression.
Levothyroxine is designed to bring thyroid hormone levels back to normal so the body can function properly. It is usually taken once a day, every day, to provide a consistent dose of the thyroid hormone.
Shelf Life of Levothyroxine
Like any medication, levothyroxine has a shelf life – the length of time the medication retains its stability and effectiveness. The shelf life for levothyroxine is typically 2 to 3 years from the date of manufacture.
The expiration date listed on the packaging is the final day the manufacturer guarantees the full potency and safety of the medication. Once past the expiration date, the medication may start to slowly degrade.
Over time, the concentration of the active ingredient can decrease. Exposure to heat, humidity, or improper storage can also speed up the breakdown of the medication. While the medication does not immediately become toxic or dangerous after the expiration date, its potency and effectiveness can no longer be guaranteed by the manufacturer.
Is it Safe to Take Expired Levothyroxine?
There is limited research specifically looking at the safety of taking expired levothyroxine. However, there are a few important considerations:
- Expired levothyroxine may have lower potency. As the medication breaks down over time, the concentration of active levothyroxine sodium may decrease. This means an expired pill may not provide the full intended dose.
- Risk of unpredictable side effects. While an expired medication is not necessarily unsafe, you cannot be certain it will react in the body the same as a fresh pill. There could be more risk of side effects.
- Possibility of bacterial contamination. Very old expired pills that have been improperly stored could potentially support bacterial growth.
Based on these risks, the general medical recommendation is to not take expired levothyroxine. An expired medication is essentially a gamble – you cannot know for certain the pill contains the labeled dose and potency.
However, the risks appear to be low if the medication has been stored properly and has expired only recently, within a few months past the expiration date. The medication has likely retained much of its original potency.
Talk to your pharmacist or doctor before taking any expired medication, including levothyroxine. They can look at the condition of the pills and advise you on the risks.
Will Expired Levothyroxine Still Be Effective?
While expired levothyroxine may not necessarily be unsafe, its effectiveness does decline after the expiration date.
Here’s what you can expect if taking expired levothyroxine:
- Gradual decrease in potency. How quickly the drug degrades depends on storage conditions. But over time, the concentration and strength of the active ingredient decreases.
- Possibility of unstable thyroid hormone levels. With lower potency, the medication may not provide enough thyroid hormone replacement. This could lead to continued hypothyroid symptoms.
- Potential need for dose adjustments. Your doctor may request more frequent blood tests to check your thyroid hormone levels. They may increase your levothyroxine dose to account for lower potency of expired pills.
Research shows that the concentration of levothyroxine can decrease by 5 to 10% in the first year after expiration. Greater reductions in potency can occur with longer expiration periods or improper storage.
To ensure you are getting the full prescribed dose, it is best to take levothyroxine before the expiration date. The manufacturer guarantees the labeled potency up until the expiration date.
If you have taken expired levothyroxine, let your doctor know so they can check your thyroid hormone levels. They may make adjustments to get your levels back into the normal range.
Does Levothyroxine Expire Faster After Opening?
Levothyroxine tablets typically come in bottles with 30, 90, or 100 tablets. Once opened, does the medication expire faster than the labeled expiration date?
There is limited research on how quickly levothyroxine degrades after opening. However, some general recommendations include:
- Refer to expiration date on bottle. Do not use if beyond expiration date.
- Write date opened on the bottle. Discard within 90 days of opening.
- Store at room temperature away from excess heat and moisture to prevent faster breakdown.
- Keep medication in original bottle to protect from light exposure.
- Do not transfer to a pill organizer. Only remove levothyroxine right before taking your daily dose.
Levothyroxine is not thought to degrade within days or weeks after opening. But following the precautions above can help prevent faster deterioration and ensure you are getting the full potency through the expiration date.
Check tablets regularly for any changes like discoloration or crumbling, which could indicate faster degradation. It is also good practice to get a new prescription before finishing your opened bottle so you always have fresh medication on hand.
Does Levothyroxine Lose Potency After the Expiration Date?
Yes, levothyroxine starts to slowly lose potency and break down after the expiration date. The expiration date is when the manufacturer stops guaranteeing the full labeled potency and stability of the medication.
While medicine does not degrade significantly within days or weeks after the expiration date, there is gradual loss of potency over time:
- Concentration decreases: Studies show the concentration of active levothyroxine sodium decreases by 5% to 10% the first year after expiration. Greater reductions in concentration occur with longer expired periods.
- Pills may chip or crumble: Expired pills may demonstrate physical signs of deterioration like chipping, color changes, or crumbling. This indicates loss of potency.
- Lower absorption: Breakdown of the tablet over time may also reduce absorption of levothyroxine from the gut into the bloodstream after taking an expired pill.
The longer levothyroxine sits past its expiration date, the less potent it becomes due to chemical degradation. Old pills may contain only 80 to 90% or even less of the original levothyroxine concentration.
Signs like changes in pill appearance or hypothyroid symptoms recurring can indicate your medication has lost potency. Check with your pharmacist or doctor if you think your levothyroxine pills are no longer fully effective.
How to Store Levothyroxine Correctly
Proper storage is important for maintaining levothyroxine potency and extending the shelf life. Here are some tips for storing levothyroxine:
- Room temperature – Keep medication at controlled room temperature between 68°F and 77°F (20°C to 25°C).
- Avoid excess heat and moisture – Do not store in humid, damp areas like bathrooms that can expose pills to moisture.
- Protect from light – Keep levothyroxine in original container to limit light exposure which can degrade the pills.
- Avoid pill organizers – Only remove pills from bottle to take your immediate daily dose to reduce air and moisture exposure.
- Check expiration date – Do not take levothyroxine that is expired. The date should be printed on the medication bottle.
Properly stored levothyroxine can maintain its labeled potency through the expiration date printed on the bottle. If stored in cool, dry conditions in the original container, it can sometimes remain stable for some time after expiration.
However, be sure to get a new prescription before finishing your bottle so you always have fresh, non-expired levothyroxine pills on hand.
Can You Take Levothyroxine After the Expiration Date?
The general medical recommendation is to not take levothyroxine after the printed expiration date. After this date, the medication is no longer guaranteed by the manufacturer to have the full labeled potency and effectiveness.
However, according to USP standards, medications retain about 90% of original concentration for up to 5 years after the labeled expiration date if properly stored.
So while there are risks like decreased potency and unpredictable side effects, taking recently expired levothyroxine within a few months past expiration poses low risk for most people. The medication has likely retained much of its potency.
But the longer after expiration, the less potent the medication becomes. Pills more than 1 to 2 years expired may have significantly reduced strength. At this point, it is not advisable to take expired levothyroxine.
To be safe, always talk to your pharmacist or doctor before taking expired levothyroxine. They can determine if the risks likely outweigh any benefits for your situation.
It is also best practice to refill levothyroxine regularly so you have a new, unexpired prescription available when finishing a bottle. Never take levothyroxine showing signs of deterioration like chipped, cracked, or discolored pills.
Does Levothyroxine Have an Extended Shelf Life?
No, levothyroxine does not have an extended shelf life beyond the labeled expiration date. The shelf life or expiration period for levothyroxine is 2 to 3 years from the manufacture date.
The manufacturer cannot guarantee potency or stability beyond the printed expiration date. Once past expiration, the medication slowly begins degrading and losing potency due to chemical breakdown.
However, levothyroxine may maintain most of its potency for some time past expiration:
- 90% potency within 5 years – Properly stored pills generally retain about 90% original concentration for up to 5 years past expiration according to USP standards.
- Up to 70% remaining at 7 years – One study found levothyroxine retained around 83% and 71% of labeled concentration at 3 and 7 years after expiration, respectively.
So while the shelf life is not extended past the expiration date, levothyroxine does appear to slowly degrade over the course of years when properly stored. Recently expired pills within months past expiration likely maintain much of their original potency and may be safe for most patients.
However, it is still generally recommended to take levothyroxine only up until the printed expiration date on the bottle for ensured potency. Do not take levothyroxine more than 2 to 3 years expired due to greater risks of severely reduced potency.
Is There an Exception to Taking Expired Levothyroxine?
In most cases, it is recommended to avoid taking expired levothyroxine due to risks like reduced potency, unpredictable effects, and potential bacterial contamination.
However, there is one scenario where a physician may advise continuing to take recently expired levothyroxine:
If absolutely no replacement thyroid hormone medication is available and thyroid hormone levels must be maintained.
This would be an extremely rare and temporary situation, like an emergency disaster where new medication cannot be accessed for a period of time.
In this case, a doctor may determine that taking recently expired levothyroxine in proper storage for a very short period poses less risk than abruptly stopping all thyroid hormone replacement.
They can monitor thyroid levels and watch for any symptoms indicating the medication is no longer adequately effective. Strict medical monitoring and control of dose and duration is essential in this scenario given the potential serious risks of taking expired medication.
This would be a short-term exception to bridge an emergency gap until fresh, non-expired levothyroxine can be obtained. Patients should never independently decide to take expired levothyroxine without consulting a physician in these rare circumstances.
In all normal circumstances, it is advised to take levothyroxine only up to the manufacturer’s expiration date on the bottle for ensured safety and potency.
Can You Take Levothyroxine After the Discard Date?
The discard or “do not use after” date on levothyroxine is very similar to the expiration date. It is the final day the manufacturer recommends using the medication.
Levothyroxine should not be taken after the discard date printed on the prescription bottle. At this point, the medication is past the manufacturer’s guarantee of potency and may start degrading.
The risks of taking levothyroxine after the discard date are similar to after expiration:
- Reduced strength and potency
- Possibility of unpredictable side effects
- Potential for bacterial contamination in very old tablets
In addition, absorption from the gut may become erratic with an old, degraded tablet. This can lead to unstable thyroid hormone levels.
The discard date and expiration date are typically very close together, within months of each other. So a medication should not be used for long after passing the discard date.
In rare cases, a doctor may advise taking recently expired medication for a very short time if absolutely no replacement is accessible. But in general, levothyroxine should not be used passed the discard or expiration date for safety and effectiveness. It is recommended to refill the prescription as needed to access fresh medication.
Is it Dangerous to Take a Double Dose of Levothyroxine?
It is generally not advised to double your levothyroxine dose without medical monitoring. Taking two pills too close together can lead to side effects of excessive thyroid hormone.
Potential risks and symptoms of an accidental double dose include:
- Racing heart rate or palpitations
- Shaking hands or tremors
- Sweating
- Anxiety or nervousness
- Difficulty sleeping
- Diarrhea or frequent bowel movements
- Unexplained weight loss
In rare cases, very high thyroid hormone levels could progress to a thyroid storm, a potentially life-threatening condition requiring emergency medical treatment.
If you accidentally take a double dose of levothyroxine, seek medical advice promptly rather than waiting it out. Your doctor may recommend holding off on your next scheduled dose and monitoring your symptoms to allow levels to normalize. Taking an antithyroid medication may sometimes be used to counter the excessive dose under medical supervision.
To avoid double dosing, be very careful to take only your prescribed daily dose. Use reminders like pill organizers or alarms. Leave your levothyroxine bottle in one designated spot to prevent confusion. Tell your doctor about any close double doses so they can adjust your care if needed.
Conclusion
In most cases, it is not recommended to take expired levothyroxine. After the printed expiration or discard date, the medication is no longer guaranteed by the manufacturer to maintain full potency and stability. While not necessarily toxic, degraded tablets come with risks of reduced effectiveness, unpredictable side effects, and unstable thyroid hormone levels.
However, levothyroxine does appear to slowly lose potency over a period of years rather than immediately degrading. Tablets stored properly may retain around 90% original concentration for up to 5 years past expiration. Very recently expired levothyroxine, such as within a few months past the expiration date, has likely maintained much of its strength and may pose low risks for most patients. But medical advice is still recommended before taking any expired medication, including levothyroxine.
To ensure you are getting the full potency of your prescribed dose, it is best to take levothyroxine only up until the expiration date on the bottle. Always keep some fresh, non-expired tablets on hand by refilling your prescription regularly before finishing your bottle. If you have taken expired levothyroxine or have any concerns about your medication, speak to your pharmacist or doctor right away. They can check your thyroid hormone levels and make any needed dose adjustments.