Key takeaways:
Over-the-counter (OTC) children’s cough, cold, and allergy medications may cause side effects like drowsiness and agitation. They may also cause more serious side effects, like hallucinations and seizures.
For children under 6 years old, you should talk to your healthcare provider before using an OTC cough or cold medicine. There may be a better choice for your child’s symptoms.
Some OTC children’s products contain several different medications. Taking extra ingredients your child doesn't need increases their risk of side effects.
When your child isn’t feeling well, it’s common to turn to an over-the-counter (OTC) medication to help them feel better. But these medications have side effects that could make your child feel worse.
When they’re used properly, the side effects of these medications are usually mild. But there are still some you should be aware of, especially in children. Below, we’ll discuss eight possible side effects and how you might manage them.
1. Drowsiness
Antihistamines and dextromethorphan are commonly found in OTC children’s medications. Both can cause drowsiness.
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Dextromethorphan is a cough suppressant. It’s usually sold in OTC products for a nagging, dry cough from a cold or the flu. Common OTC products containing dextromethorphan include Delsym and Robitussin 12-Hour Cough Relief.
Antihistamines treat allergies and cold symptoms, like sneezing or runny nose. Older antihistamines, called first-generation antihistamines, typically cause the most drowsiness.
Common first-generation antihistamines include:
Diphenhydramine (Benadryl)
Brompheniramine (an ingredient in Dimetapp Cold & Allergy)
Chlorpheniramine (an ingredient in Triaminic Multi-Symptom Fever & Cold)
If drowsiness is an issue for your child, ask your healthcare provider about trying a different type of antihistamine, like loratadine (Claritin). They may cause less drowsiness, but may not be as effective for symptoms that aren’t caused by allergies.
2. Agitation
Agitation is a side effect of some medications — especially for children. You may notice your child acting in an aggressive, excited, or stubborn manner that isn’t usual for them.
As mentioned, first-generation antihistamines usually cause sedation or drowsiness. But in some children, they can have the opposite effect — agitation and hyperactivity. Agitation could also be a sign your child’s dose is too high.
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Decongestants can also cause signs of agitation in children. Pseudoephedrine and phenylephrine can cause nervousness, trouble sleeping, or a fast heartbeat. And children in particular can be overstimulated by these medications.
Children’s OTC decongestants available include:
Pseudoephedrine (Sudafed)
Phenylephrine (Sudafed PE, Neo-synephrine Cold+Allergy)
Using OTC medications as directed can help avoid agitation in children. If this side effect occurs, it should go away after your child stops taking the medication. If it doesn’t, be sure to talk to your healthcare provider to determine if there’s something else causing it.
3. Constipation
Constipation is a possible side effect of dextromethorphan and antihistamines. These medications can slow down the way food moves through your child’s intestines. Slower movement may lead to constipation.
It’s important to make sure your child stays hydrated to help prevent constipation. This is especially true when they’re sick and may not be eating as much as normal. If constipation becomes a problem, talk to your healthcare provider or pharmacist. They may be able to suggest an OTC option to treat it.
4. Nausea
Dextromethorphan and guaifenesin (Robitussin, Mucinex) can both cause nausea.
As mentioned earlier, dextromethorphan is a cough suppressant used for dry cough. Guaifenison helps thin mucus. And they are often found in the same medication, like Robitussin DM.
Taking these medications with food may help prevent nausea. But if that doesn’t help, talk to your healthcare provider about other options for your child’s symptoms.
5. Fast heartbeat
Children taking antihistamines and decongestants may experience changes in their heart rate. Some children may not notice their heart is racing. However, others could feel lightheaded, faint, or have problems catching their breath.
Children who also take stimulants for attention-deficit hyperactivity disorder (ADHD) may be at greater risk for this side effect.
Check in with a healthcare provider if your child is experiencing this side effect. It should go away once the medication is stopped. But if your child complains of pain in their chest or is acting oddly, you should seek medical care right away.
6. Hallucinations
Pseudoephedrine treats nasal congestion. It has the rare side effects of psychosis and hallucinations in children.
Symptoms of this include:
Seeing and hearing things that aren’t there
Extreme anxiety
Excessive talking
Extreme agitation
This side effect occurs more often with high doses or overuse of pseudoephedrine. If these symptoms appear, stop the medication and contact your healthcare provider right away.
7. Seizures
Some OTC medications increase the risk of seizures. Studies show antihistamines, decongestants, and dextromethorphan all have this risk.
Too much of these medications are more likely to lead to seizures. It’s recommended to follow dosing instructions carefully. And if your child has a history of seizures, be sure to contact your healthcare provider. They can help you choose a medication that’s safe for your child to take.
8. Serotonin syndrome
Serotonin syndrome is a build up of too much serotonin in the body — and it can be dangerous. The good news is, it’s usually very rare.
Dextromethorphan is one medication that increases serotonin levels in the body. If your child is taking another medication that increases serotonin, like an antidepressant, adding dextromethorphan could cause levels to go too high.
Symptoms of serotonin syndrome include:
Rapid heart rate
Muscle stiffness
Spasms
Confusion
Nausea and vomiting
Your child should receive medical attention immediately if these symptoms occur.
If your child is taking antidepressants, be sure to talk to your healthcare provider about which cough and cold medications are safe for them.
When should you give an OTC cough, cold, or allergy medication to your child?
You should always speak to your healthcare provider or pharmacist before choosing an OTC medication for your child. They can help recommend a product that’s safe. They can also review the dosing to make sure you know how to give it safely.
For most children, OTC cough and cold medications haven’t been shown to have much benefit. And they all come with significant risks when used by children. Non-medicated options, like saline nasal spray, seem to work better — and don’t have the same risks.
Most OTC packaging gives dosing instructions for children age 6 and older. The FDA warns to use caution when giving OTC cough and cold medications to children under the age of 4. And antihistamines and decongestants shouldn’t be used at all in children under 2 years old.
What about combination cough, cold, and allergy products for children?
Combination products can provide quick, convenient relief. Popular brands often use 2 or more ingredients to treat different symptoms at one time. Medications for pain and fever, like acetaminophen (Tylenol) or ibuprofen (Advil or Motrin), may also be added.
Your child may have more side effects with combination products. Following age-appropriate dosing instructions can help avoid misuse and side effects.
It’s also important to review active ingredients to avoid overmedication. Active ingredients and what they’re for are listed on the "Drug Facts" label. Looking over the list can help you choose a product that has the right medications for your child’s symptoms.
If there are symptoms listed on the label your child doesn’t have, don’t use that medication. Giving your child a medication they don’t need just increases the risk of side effects.
When in doubt, ask your pharmacist or healthcare provider. Labels can be tricky, and it’s always a good idea to ask for help.
The bottom line
When your child is sick, your healthcare provider may suggest turning to an OTC children’s cough, cold, or allergy medication. But it’s important to be aware of common side effects that can happen during treatment. Drowsiness and agitation are the most common side effects of these medications. But more serious side effects, like hallucinations and seizures, are also possible.
It’s important to pay attention to your child’s age and symptoms when choosing an OTC product. Never use an OTC cold medication for a child under 4 without talking to your healthcare provider first.
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References
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