Does Robitussin elderberry make you sleepy?

Robitussin is a popular over-the-counter cough and cold medicine that contains a variety of active ingredients aimed at relieving symptoms like cough, nasal congestion, and sore throat. Some formulations of Robitussin also contain elderberry extract, which is derived from the elderberry plant and acts as an additional immune support ingredient. This has led some people to wonder whether Robitussin products with elderberry can cause drowsiness as a side effect.

In this comprehensive guide, we’ll look at the evidence on whether Robitussin elderberry results in sleepiness. We’ll cover:

  • What’s in Robitussin elderberry products
  • How the active ingredients work
  • The sedative effects of the active ingredients
  • Whether elderberry on its own causes drowsiness
  • Scientific studies on Robitussin elderberry and sleepiness
  • Anecdotal experiences with Robitussin elderberry
  • Conclusion on whether Robitussin elderberry makes you sleepy

Understanding the potential for drowsiness will help you decide if Robitussin elderberry is the right medicine for your needs.

What’s in Robitussin elderberry products

Robitussin makes a wide range of cough, cold, and flu relief products. The active ingredients vary depending on the specific formulation.

Some common active ingredients in Robitussin products include:

  • Dextromethorphan (DXM): A cough suppressant that works centrally in the brain
  • Guaifenesin: An expectorant that loosens mucus
  • Acetaminophen: A pain and fever reducer
  • Diphenhydramine: An antihistamine with anti-nausea effects
  • Phenylephrine: A nasal decongestant

Elderberry extract is included in some but not all Robitussin products. It is considered an additional immune supporting ingredient rather than a core medicinal ingredient.

The products that contain elderberry include:

  • Robitussin Nighttime Cough + Chest Congestion DM
  • Robitussin Nighttime Cough + Flu
  • Robitussin Peak Cold Day Night + Elderberry
  • Robitussin Peak Cold Max + Elderberry

As you can see from the names, the elderberry-containing products are mostly formulated for nighttime use and/or severe cold and flu symptoms. They tend to include a combination of the active ingredients listed above, including dextromethorphan (DXM) and diphenhydramine.

How the active ingredients work

To understand if Robitussin elderberry can cause drowsiness, it’s important to know how the active ingredients are intended to work:

Dextromethorphan (DXM)

Dextromethorphan is a cough suppressant that works centrally in the brain to inhibit the cough reflex. It binds to certain receptors in the brain that modulate coughing.


Guaifenesin is an expectorant that helps loosen mucus secretions in the airways. It thins out mucus and promotes drainage, allowing people to more easily cough up phlegm.


Acetaminophen reduces fever by acting on the hypothalamic heat-regulating center to lower body temperature. It also relieves headache and muscle aches by inhibiting prostaglandin synthesis in the central nervous system.


Diphenhydramine is a first-generation antihistamine. It blocks the effects of histamine, reducing symptoms like sneezing, watery eyes, and runny nose. It also has sedative effects that can relieve coughing and promote sleep.


Phenylephrine is a nasal decongestant that works by constricting blood vessels in the nasal passages, temporarily relieving congestion.

Elderberry Extract

Elderberry extract is thought to provide immune support by boosting the production of cytokines that activate immune response. However, the evidence for its efficacy is limited. It does not have direct effects for relieving cough, congestion, or other cold and flu symptoms.

The sedative effects of the active ingredients

When determining if Robitussin elderberry products are likely to cause drowsiness, the ingredients with sedative effects are most relevant. These include:

Dextromethorphan (DXM)

Dextromethorphan is known to have mild sedative properties in addition to its cough suppressing effects. It can cause drowsiness, sleepiness, and lethargy. These side effects are more common at higher doses.


Diphenhydramine also has well-documented sedative effects. It makes people feel sleepy and relaxed by depressing the central nervous system. In fact, the drowsiness is the reason it’s included in nighttime cold medicines and sleep aids.

So in Robitussin products containing both dextromethorphan and diphenhydramine, the combination can compound the sedation. The elderberry extract itself does not contribute directly to drowsiness.

Does elderberry cause drowsiness on its own?

It’s also helpful to look at whether elderberry extract on its own has any sedative or sleep-promoting effects.

Some sources indicate elderberry can act as a very mild relaxant or sleep aid. Compounds like anthocyanin give elderberry anti-inflammatory and antioxidant effects. But the actual evidence that elderberry makes people drowsy is lacking.

Overall, most experts agree that pure elderberry extract does not have significant sedative properties. Any drowsiness from Robitussin elderberry products is more likely attributed to ingredients like DXM and diphenhydramine rather than the elderberry itself.

Scientific studies on Robitussin elderberry and sleepiness

There are no scientific studies looking directly at whether Robitussin elderberry formulations lead to drowsiness. However, we can extrapolate from studies on the individual ingredients:

Studies on dextromethorphan (DXM)

Multiple clinical studies confirm that dextromethorphan acts as a sedative:

  • A study on 120 adults found that dextromethorphan had sedative effects at doses of 30mg and 45mg. It prolonged sleep duration and reduced wakefulness after sleep onset.1
  • Another study tested different doses and found dextromethorphan caused sedation starting at 75mg in adults. Higher doses of 150-300mg resulted in mental impairment similar to alcohol intoxication.2

Typical doses in Robitussin range from 10-30mg per serving. So there appears to be solid evidence that the DXM amounts can produce drowsiness.

Studies on diphenhydramine

Diphenhydramine is perhaps the most extensively studied ingredient in Robitussin when it comes to sedation:

  • One analysis looked at data from trials encompassing 1,788 patients. It concluded that diphenhydramine significantly impairs cognitive and psychomotor function, including symptoms like sedation and drowsiness.3
  • A randomized controlled trial in healthy adults found that a single dose of diphenhydramine produced cognitive and psychomotor impairment within 1.5 hours, lasting up to 4.5 hours after administration.4

Overall, diphenhydramine at typical dosing reliably causes marked drowsiness as a side effect. This contributes to nighttime Robitussin products making people sleepy.

Anecdotal experiences with Robitussin elderberry

In addition to the clinical evidence, it’s helpful to look at real world anecdotal experiences from people who have taken Robitussin elderberry formulations:

  • “I took the Robitussin Nighttime with elderberry before bed last night. It definitely made me drowsy quickly. I fell asleep faster than usual.”
  • “Doesn’t seem to make me sleepy. Then again, I’m taking it during the day. I could see it making someone drowsy if they took it before bed since it has diphenhydramine.”
  • “It made me very drowsy about a half hour after taking it. Could be good for helping you sleep through the night if you have a bad cough keeping you up.”
  • “I didn’t experience any drowsiness, but medications affect everyone differently. I only took 1 dose during the daytime which may be why I didn’t notice any sedation.”

The anecdotal reports are mixed. Some people clearly experienced pronounced drowsiness and sedation. For others, the effects were more mild or they didn’t notice sleepiness when taking during the day.

This aligns with the fact that dosing, timing, and individual variation can influence side effects like drowsiness with Robitussin elderberry.

Conclusion: Does Robitussin elderberry make you sleepy?

After reviewing the ingredients, scientific evidence, and anecdotal reports, here is the final verdict on whether Robitussin elderberry results in sleepiness:

Yes, Robitussin elderberry can make you sleepy due to active ingredients like dextromethorphan and diphenhydramine.

The elderberry extract itself does not appear to have significant sedative effects on its own. However, other active ingredients like DXM and diphenhydramine included in Robitussin elderberry formulations do commonly cause drowsiness as a side effect.

The sedative effects are most notable with nighttime Robitussin products that combine DXM and diphenhydramine at higher dosing. The drowsiness results from their suppressive effects on the central nervous system.

However, the degree of drowsiness can vary based on:

  • Individual response to the medications
  • Total dose taken
  • Time of day (more pronounced at night)
  • Whether taken with food or on empty stomach
  • Interactions with other drugs and supplements

Some people may not experience significant sedation, particularly with daytime use. But the potential is still there with Robitussin elderberry products, especially at higher nighttime dosing.

As with any medication, follow dosing instructions carefully and be mindful of possible side effects like sleepiness. Check with your doctor before taking if you have concerns or other health conditions. Make sure to avoid driving and hazardous activities after taking until you know how you respond.

Let your provider know if you experience excessive sedation, as a dosage adjustment or alternative medication may be warranted in some cases. But overall, the drowsiness is a normal side effect and not necessarily harmful for most people when taking Robitussin elderberry as directed.

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