Key takeaways:
Look-alike, sound-alike (LASA) medications are those whose names look or sound similar. LASA medications are easy to mix up, both in healthcare settings and at home by people who use them.
One example of LASA medications is Celebrex (a pain reliever) and Celexa (an antidepressant). Another example is bupropion (an antidepressant) and buspirone (an anxiety medication). Many insulins also have similar names, such as Humalog and Humulin R.
Accidentally taking the wrong medication can lead to unwanted or dangerous side effects. This is especially true with high-risk medications such as insulins and opioids.
You can help prevent LASA medication errors by maintaining an updated medication list. Read all prescription and over-the-counter labels before taking medications. If you don’t recognize a medication, a pharmacist can help identify it for you.
Imagine picking up two prescriptions that have very similar-sounding names. But you know the medications treat different health conditions. These are called look-alike, sound-alike (LASA) medications. And they can add an extra layer of confusion when it comes to organizing your medications.
More concerning, it can be easy to mix up LASA medications. This seemingly small mistake could have a potentially large impact on your health. Missing a dose of medication could mean leaving your condition untreated. And taking a medication you don’t need could lead to unwanted or even dangerous side effects.
Being aware of medications with similar names is a good first step to take in staying safe. But there are other tips you can try to help avoid mixing up LASA medications.
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What are look-alike, sound-alike medications?
LASA medications are those whose names look or sound similar. The term also includes medications or medication packaging that look similar. Healthcare professionals and consumers alike can mix up LASA medications.
For example, Celebrex (a pain reliever) and Celexa (an antidepressant) treat different conditions. But their names use many of the same letters and can be confused for each other.
Mixing up LASA medications causes two main problems. Not taking the medication you intended can leave symptoms or health conditions untreated. And being exposed to a medication when you shouldn’t have been can lead to unexpected side effects.
Some LASA mistakes may only cause mild side effects, such as dizziness or headaches. But others could lead to dangerous complications, such as trouble breathing. In the most serious cases, LASA mix-ups can be life threatening.
7 examples of look-alike, sound-alike (LASA) medications
There are hundreds of LASA medications. Below is a list of seven examples and what could happen if you take the wrong medication.
1. Acetaminophen and acetazolamide
Acetaminophen (Tylenol) and acetazolamide are one example of LASA medications. Acetaminophen is an over-the-counter (OTC) pain reliever and fever reducer. Acetazolamide is a prescription-only medication used to treat altitude sickness and reduce swelling. It’s also sometimes prescribed for glaucoma or seizures.
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At normal doses, acetaminophen is usually well tolerated. So if you take it by mistake, it most likely won’t cause serious harm. But you may experience minor side effects, such as nausea.
Acetaminophen isn’t risk free, though. One serious side effect is liver damage. The risk for liver damage is higher if someone takes too much or combines it with large amounts of alcohol. Rarely, acetaminophen can cause severe skin reactions, including Steven-Johnson syndrome.
Acetazolamide can cause side effects such as tingling in the hands or feet or fatigue. Because it helps remove excess fluid from the body, it can also make you have to urinate more than usual. In severe cases, this can cause dehydration or electrolyte imbalances, such as low potassium levels.
Acetazolamide is also a sulfa medication. So if you have a sulfa allergy, you could experience an allergic reaction to the medication.
2. Bupropion and buspirone
Another LASA medication example is bupropion (Wellbutrin SR, Wellbutrin XL) and buspirone. Bupropion is an antidepressant used to manage depression and help people stop smoking. Buspirone is an anti-anxiety medication.
If you take buspirone instead of bupropion, your depression symptoms may worsen or feel less managed. If you’re taking bupropion to quit smoking, you may have stronger nicotine cravings or find it harder to stop. If you take bupropion instead of buspirone, your anxiety could worsen.
If you’ve been taking bupropion and suddenly stop, you could also have withdrawal symptoms. These include nausea, flu-like symptoms, and trouble sleeping.
Common side effects of bupropion include trouble sleeping, tremors, and anxiety. You would most likely experience these side effects if you took bupropion by mistake. But the medication also carries a risk for more serious side effects, such as seizures and elevated blood pressure.
Buspirone’s mild side effects are similar to bupropion’s. These include trouble sleeping, agitation, and dizziness. In rare cases, buspirone can cause serotonin syndrome. This is when there’s too much serotonin in your brain and body. In severe cases, serotonin syndrome can become life threatening.
3. Celebrex and Celexa
Another LASA medication example is Celebrex (celecoxib) and Celexa (citalopram). Celebrex is an anti-inflammatory that helps relieve pain. Celexa is an antidepressant.
If you accidentally take Celexa instead of Celebrex, your pain may feel more intense. If you take Celebrex instead of Celexa, your depression symptoms may worsen. What’s more, suddenly stopping Celexa can cause withdrawal symptoms.
Taking Celebrex by accident could cause digestive side effects such as diarrhea or an upset stomach. But it also carries some serious risks. These include stomach ulcers, liver or kidney damage, and a higher risk of heart attacks. These risks are more of a concern when you’re taking Celebrex long term. But it’s possible for these side effects to occur even if you only take a dose or two by mistake.
For Celexa, common side effects include nausea, dry mouth, and sleep changes. These are the side effects most likely to occur if you take Celexa by accident. But the medication also carries a risk of seizures and abnormal heart rhythms. Serotonin syndrome and low sodium levels are other rare but potentially serious side effects.
4. Clomipramine and clomiphene
Clomipramine (Anafranil) and clomiphene (Clomid) are another notable LASA medication pair. Clomipramine is an antidepressant that helps treat obsessive-compulsion disorder (OCD). Clomiphene is a fertility medication.
If you take clomipramine instead of clomiphene, you most likely won’t have the fertility effects you were hoping for. If you take clomiphene instead of clomipramine, you may notice worsened OCD symptoms. Suddenly stopping clomipramine can also cause withdrawal symptoms.
Clomipramine may cause side effects such as drowsiness, dizziness, and constipation. But in rare cases, the medication can cause seizures or heart rhythm problems.
Taking clomiphene by accident could cause hot flashes, breast tenderness, or nausea. It can also lead to ovarian hyperstimulation syndrome (enlarged ovaries), or OHSS. In severe cases, OHSS can be dangerous.
5. Hydroxyzine and hydralazine
Another pair of LASA medications is hydroxyzine (Vistaril) and hydralazine. Hydroxyzine is an antihistamine used to manage anxiety and relieve itching due to allergies. Hydralazine is a medication used to lower blood pressure.
If you take hydroxyzine instead of hydralazine, your blood pressure may go up. This could lead to headaches, dizziness, or chest pain. In severe cases, this could raise your risk of heart-related problems, such as a heart attack. If you take hydralazine instead of hydroxyzine, you may notice worsened anxiety or itching.
Hydroxyzine’s common side effects include drowsiness, dizziness, and dry mouth. These are the issues most likely to occur if you took it by mistake. But the medication does have a risk of abnormal heart rhythms and seizures, although these are rare.
Hydralazine’s common side effects include headache, upset stomach, and dizziness. But you may also experience a sudden increase in your heart rate. This could cause chest pain and, in severe cases, trigger a heart attack.
6. Insulins
Insulin products are another important group of LASA medications. There are different types of insulin, and several have names that can be easily confused. Visual similarity adds to the risk. Many insulin pens and vials have similar shapes, colors, and labels.
Insulins differ in how quickly they start working and how long they last:
Rapid-acting insulins: Start working in 15 minutes and last for about 2 to 4 hours
Regular insulin: Start working in 30 minutes and last for about 3 to 6 hours
Intermediate-acting insulins: Start working in 1 to 2 hours and last for about 12 hours
Long-acting insulins: Start working in 2 to 4 hours and last for up to 24 hours
Ultra-long-acting insulins: Start working in 6 hours and last for 36 to 42 hours
Insulins are an example of a high-risk medication. This means a small change in dose can have large effects when it comes to how the medication works and your risk of side effects.
If you use a rapid-acting insulin instead of a long-acting one, your blood sugar (glucose) could quickly drop. This could cause low blood sugar (hypoglycemia). Common symptoms of low blood sugar include sweating, shakiness, and dizziness. But severe cases can be life threatening, especially if left untreated.
If you inject a long-acting insulin instead of a rapid-acting one, your blood sugar may stay higher than expected. Very high blood sugar (hyperglycemia) is also possible. Repeated mix-ups like this can affect your overall diabetes treatment goals.
Examples of LASA insulins include:
Humalog and Humulin R: Humalog (insulin lispro) is a rapid-acting insulin. Humulin R (human insulin) is a regular insulin.
Novolin R and Novolin H: Novolin R is a regular insulin. Novolin N (insulin NPH) is an intermediate-acting insulin.
Lantus and Toujeo: Lantus and Toujeo both contain insulin glargine (a long-acting insulin). And their injector pens look similar. But Toujeo provides a higher dose than Lantus.
7. Opioid pain relievers
Opioid pain relievers are another class of medication that’s easy to mix up. There are many different opioids, and several have similar-sounding names or overlapping appearances. Opioid mix-ups can occur between different doses of the same medication. They can also happen with different opioids that come in similar packaging.
Opioids vary in potency. This means the dose needed to achieve the same level of pain relief differs greatly. For example, hydromorphone (Dilaudid) is 5 to 10 times more potent than morphine (MS Contin). Confusing a low-potency opioid with a high-potency one can have serious consequences. This is why opioids are considered a high-risk medication.
If you take a more potent opioid by mistake, you could experience severe drowsiness, confusion, or slowed breathing. In the most severe cases, this can lead to unconsciousness, dangerously low oxygen levels, or death.
If you take a less potent opioid than what you’re used to, your pain may not be as well managed. This could lead people to take extra doses to try to relieve their pain. This raises the risk of side effects and potential overdose.
Other examples of LASA opioids include:
Oxycodone and OxyContin: OxyContin is a long-acting version of oxycodone that typically contains higher doses.
Oxycodone and hydrocodone: Oxycodone is slightly more potent than hydrocodone. Each opioid also has a version available that combines them with acetaminophen.
Hydrocodone and hydromorphone: Hydromorphone is several times more potent than hydrocodone.
Why are look-alike, sound-alike medications concerning?
LASA medications are a concern because they can lead to medication errors. This can include mistakes in several settings, such as:
When a person has multiple LASA medications at home and is taking their doses
When a healthcare professional is prescribing medications
When a pharmacist is dispensing medications
When a medication distributor is shipping medications to pharmacies
When a manufacturer is making and packaging medications
When a nurse or medical assistant is administering medications in a hospital
Some estimates suggest that as much as 25% of all medication errors are due to LASA medication mix-ups. And in the most severe cases, these mistakes can be fatal.
These mistakes are especially dangerous with high-risk medications. That’s because even small dose changes in these medications can have a significant impact on the risk of side effects. As discussed above, mixing up insulins can cause severely low blood sugar. And taking the wrong opioid could lead to slowed breathing or overdose.
How can you prevent mistakes with look-alike, sound-alike medications?
Most ways to prevent mix-ups with LASA medications happen behind the scenes — at drug companies, hospitals, and pharmacies. But there are still steps you can take on your own to stay safe with your medications.
The following tips can help you limit or prevent LASA errors at home:
Know what you take. Knowing the name, dose, and reason for each medication you take is the first step in staying safe. If you’re unsure why you’re taking something, ask your pharmacist or prescriber. Keeping an updated medication list can help you catch errors.
Read your medication labels. Double check your prescription and OTC medication labels before taking something. Carefully read both the brand and generic names. And review the dose, formulation, and directions each time you take a medication.
Ask if something looks different. If your medication has a new color, shape, or label, ask your pharmacist if it’s the same medication as the last time you got it filled. Most times, the change is harmless. Generic medications often look different from brand-name versions. They can also look different from other generic versions of the same medication. But it’s good to double check instead of just assuming it’s OK.
Consider how you store medications. Keep your medications in their original containers with labels intact. Avoid combining different pills in one bottle. Consider storing LASA medications separately (maybe even in different areas of your home). And be careful if you’re using pill organizers. You may want to avoid using them for LASA medications, as this can make it harder to tell them apart.
The bottom line
Look-alike, sound-alike (LASA) medications are those that have similar sounding names. The medications or their packaging may also look visually similar. It can be easy to mix up LASA medications. Confusing one medication for another can leave a condition untreated. It can also cause unwanted or even dangerous side effects.
One example of LASA medications is Celebrex (a pain reliever) and Celexa (an antidepressant). Another example is bupropion (an antidepressant) and buspirone (an anxiety medication). Many insulins are also easily confused for each other, such as Humalog and Humulin R.
Knowing what medications you take is one of the best ways to stay safe. Keep an updated medication list and carefully read all labels before taking a dose of any of your medications. If something looks different than usual, ask your pharmacist before taking it.
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References
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