Promethazine DM Syrup

Promethazine is a phenothiazine derivative that acts as a first-generation antihistamine (H1-receptor antagonist) with significant sedative, antiemetic, and anticholinergic properties. It blocks histamine's effects on capillaries, bronchial smooth muscles, and GI smooth muscles. Dextromethorphan is a non-opioid antitussive that acts centrally on the cough center in the medulla oblongata, elevating the cough threshold. Its mechanism is thought to involve antagonism of NMDA receptors and agonism of sigma-1 opioid receptors.

Urgent Side Effects: Seek Medical Help Right Away

Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:

Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of high or low blood pressure, including:
+ Severe headache or dizziness
+ Passing out or changes in eyesight
Abnormal heart rhythms, such as:
+ Fast or slow heartbeat
Urination problems
Movement disorders, including:
+ Trouble controlling body movements
+ Twitching
+ Changes in balance
+ Difficulty swallowing or speaking
Shakiness
Hallucinations (seeing or hearing things that are not there)
Mood changes
Ringing in the ears
Seizures
Unexplained bruising or bleeding
Changes in eyesight
Feeling nervous and excitable
Trouble sleeping
* Yellow skin or eyes

Neuroleptic Malignant Syndrome (NMS): This is a rare but potentially life-threatening condition. Seek medical help immediately if you experience:
+ Fever
+ Muscle cramps or stiffness
+ Dizziness
+ Severe headache
+ Confusion
+ Changes in thinking
+ Fast heartbeat
+ Abnormal heartbeat
+ Excessive sweating

Breathing Problems: This medication may cause severe and potentially life-threatening breathing problems. Seek medical help immediately if you experience:
+ Slow, shallow, or troubled breathing

Low White Blood Cell Count: This medication may increase the risk of infection due to a low white blood cell count. If you have a history of low white blood cell count, inform your doctor. Seek medical help immediately if you experience:
+ Fever
+ Chills
+ Sore throat

Other Side Effects

Most people do not experience severe side effects, and some may only have minor side effects. However, if you notice any of the following symptoms, contact your doctor or seek medical attention if they bother you or do not go away:
+ Dizziness
+ Drowsiness
+ Fatigue
+ Weakness
+ Dry mouth
+ Upset stomach or vomiting

Reporting Side Effects

If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before Taking This Medication: Important Information to Share with Your Doctor

It is essential to inform your doctor about the following:

Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have any of the following health conditions:
+ Asthma or other breathing problems, such as chronic obstructive pulmonary disease (COPD) or sleep apnea (breathing difficulties during sleep).
+ A persistent cough that produces a significant amount of mucus, a long-term cough caused by smoking or exposure to smoke, or lung conditions like asthma or emphysema.
If you have taken certain medications for depression or Parkinson's disease within the last 14 days, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline, as this may lead to severely high blood pressure.
If you are currently taking linezolid or methylene blue, as these medications may interact with this drug.

This list is not exhaustive, and it is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health problems with your doctor and pharmacist. They will help determine whether it is safe to take this medication with your existing health conditions and medications. Never start, stop, or adjust the dosage of any medication without consulting your doctor first.

It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Adhere strictly to the dosage instructions provided by your doctor, as taking more than prescribed may increase your risk of experiencing severe side effects. Additionally, do not take this medication for a longer duration than recommended by your doctor.

Until you are aware of how this medication affects you, it is advisable to avoid driving and other activities that require alertness. Be aware that this medication may interfere with certain laboratory tests, so it is crucial to notify all your healthcare providers and laboratory personnel that you are taking this drug.

If you have diabetes (high blood sugar), it is necessary to monitor your blood sugar levels closely while taking this medication. Furthermore, this medication may cause false results in some pregnancy tests, so it is important to discuss this with your doctor.

Before consuming alcohol, using marijuana or other forms of cannabis, or taking prescription or over-the-counter drugs that may cause drowsiness, consult with your doctor. You may be more susceptible to sunburn while taking this medication, so it is recommended to avoid exposure to the sun, sunlamps, and tanning beds, and to use sunscreen and protective clothing and eyewear.

This medication may increase the risk of seizures in certain individuals, including those with a history of seizures. Discuss your risk of seizures with your doctor. If you are 65 years or older, use this medication with caution, as you may be more prone to side effects.

It is vital to inform your doctor if you are pregnant, plan to become pregnant, or are breastfeeding, as you will need to discuss the potential benefits and risks of this medication to both you and your baby.

• MAO inhibitors (concurrent use or within 14 days of stopping MAOIs due to risk of serotonin syndrome with dextromethorphan)
• Other CNS depressants (in children < 2 years old due to increased risk of respiratory depression with promethazine)

• Alcohol (additive CNS depression)
• Other CNS depressants (e.g., opioids, benzodiazepines, barbiturates, tricyclic antidepressants, other antihistamines, muscle relaxants - additive CNS depression, respiratory depression)
• Anticholinergic drugs (e.g., atropine, scopolamine, tricyclic antidepressants - additive anticholinergic effects like dry mouth, blurred vision, urinary retention, constipation)
• CYP2D6 inhibitors (e.g., fluoxetine, paroxetine, quinidine, amiodarone, bupropion - can significantly increase dextromethorphan and dextrorphan levels, leading to increased side effects and serotonin syndrome risk)
• Serotonergic drugs (e.g., SSRIs, SNRIs, triptans, linezolid, tramadol, St. John's Wort - increased risk of serotonin syndrome with dextromethorphan)
• Epinephrine (promethazine may reverse the vasopressor effect of epinephrine)

• Antihypertensives (promethazine may cause orthostatic hypotension)
• Dopamine agonists (promethazine has dopamine blocking effects)
• Phenytoin (promethazine may alter phenytoin levels)
• Metoclopramide (additive CNS depression, extrapyramidal symptoms)

• Not available

• Excessive drowsiness or sedation
• Dizziness or lightheadedness
• Difficulty breathing or shallow breathing
• Confusion or disorientation
• Hallucinations or unusual thoughts (especially with high doses of dextromethorphan)
• Dry mouth, blurred vision, urinary retention, constipation
• Nausea or vomiting
• Rash or allergic reaction
• Signs of serotonin syndrome (agitation, hallucinations, rapid heart beat, fever, sweating, shivering, muscle stiffness or twitching, loss of coordination, nausea, vomiting, diarrhea)

Category C. Use only if the potential benefit justifies the potential risk to the fetus. Promethazine has been associated with transient fetal bradycardia in some cases. Dextromethorphan is generally considered low risk.

L3 (Moderately Safe). Promethazine is excreted into breast milk and can cause sedation, irritability, or respiratory depression in the infant, especially in neonates or premature infants. Dextromethorphan is also excreted into breast milk, but infant effects are less common. Use with caution, monitor infant for drowsiness or breathing difficulties. Consider alternative if possible, especially in newborns.

Contraindicated in children younger than 2 years due to the risk of fatal respiratory depression (Black Box Warning). Use with extreme caution in children 2 years and older; lower doses and careful monitoring are essential. Avoid concomitant use with other CNS depressants. Risk of paradoxical excitation in some children.

Increased susceptibility to anticholinergic effects (e.g., dry mouth, blurred vision, urinary retention, constipation), sedation, and orthostatic hypotension. Start with lower doses and titrate carefully. Increased risk of falls. Avoid in elderly patients with dementia-related psychosis.

• Promethazine DM is contraindicated in children under 2 years of age due to the risk of fatal respiratory depression.
• Exercise extreme caution when prescribing to children 2 years and older, and ensure parents understand the dosing and risks.
• Warn patients about additive CNS depression with alcohol and other sedatives.
• Advise patients to avoid driving or operating machinery until they know how the medication affects them.
• Be aware of the potential for serotonin syndrome when co-administered with other serotonergic drugs or MAOIs (contraindicated).
• Promethazine can cause photosensitivity; advise patients to use sun protection.
• This combination is not for chronic cough, only for acute, self-limiting cough and cold symptoms.

• Single-agent Dextromethorphan (e.g., Robitussin DM)
• Guaifenesin (expectorant)
• Benzonatate (non-narcotic antitussive)
• First-generation antihistamines (e.g., diphenhydramine, chlorpheniramine) for allergy symptoms
• Second-generation antihistamines (e.g., loratadine, cetirizine) for allergy symptoms (less sedating)
• Nasal decongestants (e.g., pseudoephedrine, phenylephrine)

If your symptoms or health issues persist or worsen, it is essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist. If you have any questions or concerns about this medication, don't hesitate to discuss them with your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When reporting the incident, be prepared to provide details about the medication taken, the amount, and the time it occurred.