Robitussin Dm vs Delsym

Listen to the article instead of reading through it.


For patients experiencing cough and congestion due to common colds or allergies, certain over-the-counter medications can help manage symptoms. Robitussin DM and Delsym are two such medicines often recommended for these conditions. They each work differently in the body but both aim at relieving coughing.

Robitussin DM is a combination of dextromethorphan, a cough suppressant that affects the signals in the brain that trigger cough reflex, and guaifenesin, an expectorant that helps loosen mucus and make coughs more productive.

On the other hand, Delsym contains only one active ingredient: dextromethorphan polistirex - which is essentially dextromethorphan coated with a type of plastic called polystyrene sulfonate. This coating allows for a slow release of medication over time — providing up to 12 hours of relief from persistent dry or wet cough.

What is Robitussin Dm?

Robitussin DM and Delsym are both over-the-counter cough suppressants, but they have different active ingredients and work in slightly different ways. Robitussin DM contains dextromethorphan, which acts on the part of the brain that triggers coughing, as well as guaifenesin to help loosen mucus in your chest. It was first approved by the FDA in 1983. This combination of effects helps not only reduce nonproductive coughing but also make productive coughs more effective.

On the other hand, Delsym is a brand name for an extended-release form of dextromethorphan without any additional drugs like guaifenesin. Its longer-lasting formulation allows it to effectively suppress a dry hacking cough for up to 12 hours at a time. While neither drug is usually associated with severe side effects, users may experience mild symptoms such as nausea or sleepiness.

What conditions is Robitussin Dm approved to treat?

Robitussin DM and Delsym are both approved for the treatment of different symptoms related to colds and coughs:

  • Temporary relief of cough caused by minor throat and bronchial irritation (such as with the common cold), in addition to help loosen phlegm/mucus (Robitussin DM)
  • A 12-hour long acting formulation that treats dry, irritating, non-productive cough due to a cold or inhaled irritants (Delsym)

How does Robitussin Dm help with these illnesses?

Robitussin DM and Delsym are both over-the-counter cough suppressant medications, but they work in slightly different ways. Robitussin DM contains two active ingredients: dextromethorphan, which works by suppressing the urge to cough; and guaifenesin, an expectorant that helps loosen mucus in your chest so you can cough it up more easily. It aims to provide relief from both a dry cough and congestion.

Delsym on the other hand is only made of dextromethorphan. This substance acts on signals in your brain that trigger the cough reflex, thus dampening this reflex and reducing your need to cough. Unlike Robitussin DM however, it does not contain any ingredient designed to help with mucus production or congestion.

Another significant difference between these two drugs is their duration of action: while Robitussin DM generally provides relief for about 4-6 hours per dose, Delsym boasts a longer-lasting effect of up to 12 hours due its special time-release formula.

What is Delsym?

Delsym is a brand name for dextromethorphan, which is a cough suppressant that affects the signals in the brain that trigger cough reflex. Delsym works by increasing the threshold for coughing in the part of your brain responsible for this action. It provides relief from non-stop coughs due to common cold or other respiratory issues without causing drowsiness. As it contains extended-release suspension, it can provide up to 12 hours of relief, distinguishing itself from regular immediate-release medications like Robitussin DM. Dextromethorphan was first approved by FDA in 1958 and since then has been widely used as an over-the-counter remedy to relieve prolonged bouts of dry hacking coughs. The fact that Delsym doesn't affect serotonin means it does not have side effects such as weight gain and sexual dysfunction (common side effects with certain antidepressants). This makes Delsym particularly beneficial for those who need long-lasting relief from their symptoms without these potential drawbacks.

What conditions is Delsym approved to treat?

Delsym is an FDA-approved medication for managing symptoms related to respiratory ailments such as:

  • Temporary relief from coughs due to common cold or inhaled irritants
  • Suppressing coughs caused by minor throat and bronchial irritation

The time-release formulation of Delsym provides a continuous, long-lasting cough control that can last up to 12 hours.

How does Delsym help with these illnesses?

Dextromethorphan, the active ingredient in Delsym, is a cough suppressant that affects the signals in the brain that trigger cough reflex. This means it works directly on the part of your brain responsible for making you want to cough. This differs from Robitussin DM which combines dextromethorphan with guaifenesin, an expectorant designed to make your coughs more productive by thinning and loosening mucus in your airways.

Delsym utilizes a time-release formula that allows it to suppress a patient's cough for up to 12 hours, compared with Robitussin DM’s immediate but shorter-acting relief. Its extended-release formulation can be particularly beneficial when managing night-time symptoms or throughout a busy workday. However, since Delsym operates primarily as a suppressant rather than an expectorant like Robitussin DM, it might not be ideal for those whose primary symptom is heavy chest congestion.

How effective are both Robitussin Dm and Delsym?

Both Robitussin DM and Delsym are proven treatments for coughs due to minor throat and bronchial irritation, although they were introduced years apart with Robitussin DM being the predecessor. They operate through different mechanisms - Delsym is a single-ingredient medication containing dextromethorphan, while Robitussin DM contains both dextromethorphan (a cough suppressant) and guaifenesin (an expectorant).

A direct comparison of these two medications isn't readily available; however, their effectiveness in managing cough symptoms can be inferred from individual studies on their active ingredients. Both have been shown to reduce the frequency and severity of coughing.

Robitussin DM aims at not only suppressing the urge to cough but also thinning mucus making it easier to clear from airways which might make it more suitable for wet or productive types of coughs.

Delsym's unique selling point is its 12-hour duration per dose, potentially providing convenient all-day or all-night relief with fewer doses required. It must be noted that while effective in reducing non-productive or dry type of a cough, Delsym does not contain an expectorant ingredient like Guaifenesin present in Robitussin DM which aids in clearing mucus.

Finally, as always when comparing medications, one should consider potential side effects: both drugs have similar profiles but may interact differently with other medications you're taking or medical conditions you may have. Always consult your healthcare provider before starting any new medication.

abstract image of a researcher studying a bottle of drug.

At what dose is Robitussin Dm typically prescribed?

Oral dosages of Robitussin DM for adults are 10-20 ml every 4 hours, but studies have indicated that 10 ml every 4 hours is generally sufficient for treating cough and chest congestion in most people. Children aged between six to under twelve years may be started on a dosage of 5-10ml every four hours. In either population, if symptoms persist after a few days or get worse, medical attention should be sought immediately. The maximum dosage that should not be exceeded within any given day is 120 ml/day for adults and children over the age of twelve; whereas it's limited to just half (60ml/day) for those aged between six and under twelve years.

As for Delsym, its adult oral dosage ranges from two teaspoons (30 mg) every twelve hours - with no more than four teaspoons (60mg) per day being advisable in any case. For kids between the ages of six through eleven years old: One teaspoon (15 mg) can initially be used; however, this amount can increase up to two teaspoons depending upon severity/persistence of symptoms - but never exceeding such an increased amount within a single day.

At what dose is Delsym typically prescribed?

Delsym treatment typically begins with a dosage of 10 ml every 12 hours for adults and children over 12 years old. For younger children (6-11 years), the dose can be reduced to 5 ml every 12 hours, while those who are even younger (4-5 years) should only receive a dosage of 2.5 ml every 12 hours. It's important to note that Delsym is not recommended for children under four without consulting a medical professional first. The maximum daily dose should not exceed two doses in any given day, which may be tested if there is no relief from symptoms after several days of treatment at this rate.

What are the most common side effects for Robitussin Dm?

Common side effects that can occur with Robitussin DM and Delsym include:

  • Dizziness, headaches
  • Sleepiness or drowsiness (somnolence)
  • Nervousness or restlessness
  • Minor stomach upset including nausea, vomiting
  • Diarrhea or constipation
  • Rash, itching skin
  • Dry mouth/throat/nose Remember to seek immediate medical attention if these common symptoms persist or get worse.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Robitussin Dm?

While both Robitussin DM and Delsym are used to treat cough, they may cause different side effects in rare cases:

  • Signs of severe allergic reaction: difficulty breathing, facial or throat swelling, skin rash or hives
  • Changes in heartbeat rhythm, like fast or pounding heartbeats
  • Experience of dizziness, shortness of breath; these could be signs of a drop in blood pressure
  • Any changes in vision such as blurring or seeing halos around lights. This can indicate an increase in your inner eye pressure.
  • Symptoms that might suggest imbalance in electrolytes - headache, confusion, slurred speech, severe weakness or muscle pain
  • If you experience nervous system reactions like rigid muscles, high fever with sweating accompanied by confusion and uneven heart rate In some extreme cases: -Severe nausea followed by vomiting and loss of coordination (serotonin syndrome)

If any such symptoms appear after using either Robitussin DM or Delsym it's crucial to seek immediate medical help. It's important to remember that each person responds differently to medication based on their body's metabolism and overall health condition.

What are the most common side effects for Delsym?

The side effects of using Delsym include:

  • Dry mouth, throat irritation
  • Slight dizziness or headache
  • Nausea or stomach upset, loss of appetite
  • Trouble sleeping (insomnia)
  • Restlessness or nervousness
  • Skin rash, itching
  • Increased urination Possible serious side effects may include:
  • Fast/irregular heartbeat Confusion and hallucinations in severe cases.

It's important to note that not everyone experiences these side effects and they are generally mild when they do occur. If you have any unusual reactions after taking Delsym, it is recommended to consult your healthcare provider immediately.

Are there any potential serious side effects for Delsym?

While Delsym is considered a safe over-the-counter cough suppressant, it's crucial to be aware of possible adverse reactions. These can include:

  • Signs of an allergic reaction such as hives; difficulty breathing; swelling in your face, lips, tongue or throat.
  • Serotonin syndrome: agitation, hallucinations, fever, sweating shivering rapid heart rate muscle stiffness twitching loss of coordination vomiting
  • Severe dizziness or anxiety
  • Little or no urination
  • Liver problems - nausea upper stomach pain itching tired feeling loss of appetite dark urine clay-colored stools jaundice (yellowing of the skin or eyes)

In case you experience any of these symptoms while taking Delsym, seek immediate medical attention. Remember that self-medication should always be done with caution and respect for dosage instructions.

Contraindications for Robitussin Dm and Delsym?

Both Robitussin DM and Delsym, along with most other cough suppressant medications, may cause certain side effects in some individuals. If you notice any severe allergic reactions such as rash, itching/swelling (especially of the face/tongue/throat), severe dizziness or trouble breathing after taking these medications, please seek immediate medical attention.

Neither Robitussin DM nor Delsym should be taken if you are currently using or have recently used monoamine oxidase (MAO) inhibitors. MAOIs need approximately two weeks to clear from your system to prevent hazardous interactions with these over-the-counter cough suppressants. Always inform your healthcare provider about all the medications you are currently taking to avoid potential drug interactions.

How much do Robitussin Dm and Delsym cost?

For the brand name versions of these drugs:

  • The price of an 8 oz bottle of Robitussin DM averages around $10, which works out to about $1.25/day based on a dosage of two teaspoons taken every four hours.
  • The price for a 5 oz bottle of Delsym (12 hour relief) averages around $20, working out to approximately $4/day.

Thus, if you are in need of longer-lasting cough and congestion relief (i.e., only needing to take medication every 12 hours), then Delsym may prove more cost-effective despite its higher upfront cost. Please note that costs should not be the primary consideration when deciding between these medications.

When considering generic versions, costs can significantly lower:

  • Generic dextromethorphan/guaifenesin syrups akin to Robitussin DM are available at prices starting from as low as $0.75/day depending on your dose.
  • Generic forms similar to Delsym start from roughly about $2–$3 per day given standard dosages.

These prices might vary depending upon your location and preferred retailers but present cheaper alternatives while retaining effectiveness comparable with their branded counterparts.

Popularity of Robitussin Dm and Delsym

Robitussin DM and Delsym are two of the most common over-the-counter cough suppressants in the US. Both have a solid reputation for providing relief from persistent coughs associated with colds, flu, or allergies.

In 2020, Robitussin DM was estimated to be used by about 5 million people in the US. It accounts for approximately 10% of all over-the-counter cough suppressant sales. The drug has been steadily increasing in popularity since it was first introduced.

Delsym, on the other hand, accounted for around 7% of OTC cough suppressant purchases with an estimate of about 3.5 million users in 2020. It differs from Robitussin DM as it contains only one active ingredient - dextromethorphan - which provides up to a full day's relief from a bothersome cough due to its time-release formulation. Despite these differences between Delsym and Robitussin DM (which also includes guaifenesin to help thin and loosen mucus), both medications remain popular choices during cold and flu season.


Both Robitussin DM and Delsym contain dextromethorphan, a cough suppressant that provides relief from nonproductive coughs. They each have a track record of use in treating symptoms associated with the common cold or allergies and are supported by numerous studies indicating their efficacy over placebo treatments. While they both help to alleviate coughing, there are some key differences between them.

Robitussin DM also contains an expectorant (guaifenesin) which helps to loosen mucus in the lungs. This makes it useful for productive as well as dry coughs, whereas Delsym is only used for dry or irritating coughs due to its lack of an expectorant component.

In terms of dosage frequency, one advantage of Delsym is its 12-hour formulation while Robitussin DM needs to be taken every four hours. However, this convenience may come at a slightly higher cost as generic versions of both drugs are available but the generic version of Robitussin DM tends to be cheaper.

The side effect profile for these medications is generally similar; however individual reactions can vary. Both can cause mild gastrointestinal upset in some people and should not be combined with other products containing dextromethorphan without medical guidance.

Patients starting either treatment must closely monitor their response and consult healthcare professionals immediately if they experience severe side effects such as rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing or changes in mood/mental state including confusion or hallucinations.