What Is Dextromethorphan?

Dextromethorphan is a central antitussive, which mainly suppresses the coughing center of the brain and acts.

This product is the d-isomer of morphine levoramyl methyl ether, which exerts a central antitussive effect by inhibiting the medullary cough center. Its antitussive strength is equal to or slightly stronger than that of codeine. No analgesic effect, long-term application without tolerance and addiction. The therapeutic dose does not inhibit breathing. Oral absorption is good, it takes effect in 15-30 minutes, the effect can be maintained for 3-6 hours, and the concentration of prototype drug in plasma is very low.

Its main active metabolite, 3-methoxymorphinane, has a high concentration in plasma, and t1 / 2 is 5 hours. It is mainly used for dry cough. It is suitable for cough when cold, acute or chronic bronchitis, bronchial asthma, sore throat, tuberculosis and other upper respiratory tract infections.

Drug Name: Dextromethorphan
Alias: Dextran, methamphetamine
Foreign name: Dextromethorphan

Main indications: Cough due to upper respiratory tract infection
Dosage: Oral, 15-30mg each time, 3 to 4 times a day
Main medication contraindications: Use with caution in patients with sputum
Dosage form: Tablets, syrups

Dextromethorphan Basic Information

Chinese name

Chinese alias: Dextran

English name: dextromethorphan

English alias: Delsym; Dextromethorfan [Czech]; d-Methorphan; Dextromorphan; Destrometerfano [DCIT];

CAS number: 125-71-3

Molecular formula: C18H25NO

Molecular weight: 271.39700

Exact mass: 271.19400

PSA: 12.4000

LogP: 3.32130

Physical and chemical properties of dextromethorphan

Density: 1.11 g / cm3

Boiling point: 394.9ºC at 760 mmHg

Flash point: 116.2ºC

Refractive index: 1.585

Vapor pressure: 1.92E-06mmHg at 25 ° C ^[1]

Dextromethorphan toxicology data

Acute toxicity data

Children's oral TDLo: 16mg / kg

Oral LD50 in rats: 116mg / kg

Rat vein LD50: 16286ug / kg

Oral LD50 in mice: 210mg / kg

Small tree skin LD50: 112mg / kg

Dog vein LDLo: 22 mg / kg

Dextromethorphan molecular structure data

1. Molar refractive index: 81.76

2. Molar volume (m3 / mol): 243.8

3. Isotonic specific volume (90.2K): 631.2

4. Surface tension (dyne / cm): 44.9

5. Polarizability (10-24cm3): 32.41

Dextromethorphan Computational Chemical Data

1. Hydrophobic parameter calculation reference value (XlogP): None

2.Number of hydrogen bond donors: 0

3.Number of hydrogen bond acceptors: 2

4.Number of rotatable chemical bonds: 1

5.Number of tautomers: none

6. Topological molecular polar surface area 12.5

7.Number of heavy atoms: 20

8.Surface charge: 0

9.Complexity: 370

10.Number of isotope atoms: 0

11. Determine the number of atomic stereocenters: 3

12. Uncertain number of atomic stereocenters: 0

13. Determine the number of chemical bond stereocenters: 0

14. Uncertain number of chemical bond stereocenters: 0

15. Number of covalent bond units: 1 ^[2]

Dextromethorphan Related Drug Instructions

Dextromethorphan classification name

Primary classification: Respiratory drugs Secondary classification: Antitussive drugs Third classification: Central non-narcotic antitussives

English name of dextromethorphan

Dextromethorphan

Dextromethorphan drug alias

Methaffin, Przelan, Methadol Hydrobromide, Dimethacin, Methomorph, Dextromethorphan, Methaffin Hydrobromide, Methophen, Coeylan, Methorate, Torfan, Romilan, Sisaal

Dextromethorphan drug dosage form

1. Meco, syrup: 60ml, 120ml, containing dextromethorphan hydrobromide 90mg and 180mg, pseudoephedrine 6mg and 12mg, chlorpheniramine 6mg and 12mg, guaifenesin 30mg and 60mg, respectively; Hemp tablets, tablets: 15mg of dextromethorphan hydrobromide, 30mg of pseudoephedrine hydrochloride, 100mg of guaifenesin; 3. White plus black cold tablets (beautiful pseudo linen tablets), tablets: daily tablets each containing 325 mg of acetaminophen, 30 mg of pseudoephedrine hydrochloride, 15 mg of dextromethorphan hydrobromide; in addition to the above ingredients, add diphenhydramine hydrochloride 25 mg to each tablet; 4. Puxilan tablets, tablets: each tablet contains hydrogen bromine 15 mg of dextromethorphan acid; 5. Lizhuzhule, tablets: each tablet contains dextromethorphan hydrobromide 15mg, pseudoephedrine hydrochloride 30mg, guaifenesin 100mg; 6. healthy infant cough, syrup: per bottle 120ml, 4.5mg of dextromethorphan hydrobromide, 2mg of chlorpheniramine, 30mg of ammonium chloride and 6mg of citric acid per 5ml.

Dextromethorphan pharmacological action

Inhibit coughing of the bulbar cough and produce antitussive effect. The antitussive effect is significant, which is roughly the same as or slightly stronger than the same dose of codeine, but has no analgesic effect. Long-term use is not addictive and tolerable. The therapeutic dose does not inhibit breathing and is fast and safe.

Dextromethorphan pharmacokinetics

After oral administration, it is completely absorbed in the gastrointestinal tract and takes effect within 10-30 minutes. When taken orally at 10-20mg, the effective time is 5-6h, and when taken at 30mg orally, the effective time can be as long as 8-12h, which is longer than the same dose of codeine, so it can be used to suppress nighttime cough to ensure sleep. The drug is metabolized in the liver and excreted from the urine as the original drug or metabolite. The plasma half-life is 5h.

Dextromethorphan indication

Dry cough or irritating dry cough caused by various reasons such as acute nasopharyngitis (cold), upper respiratory tract infection, acute and chronic bronchitis, pneumonia, tuberculosis, pleurisy, myocarditis, and tumor.

Dextromethorphan contraindications

People with a history of mental illness are disabled.

Dextromethorphan notes

1. Use with more phlegm. 2. Use with caution in pregnant women.

Dextromethorphan adverse reactions

1. Occasionally atropine-like effects such as mild dry mouth, dizziness, belching, nausea, and constipation. The above reaction can disappear by itself after stopping the medicine. 2. Overdose can cause excitement, insanity and respiratory depression. It is reported abroad that naloxone can be used to rescue overdose.

Dextromethorphan dosage

Oral: 30mg each time, 3 times a day.

Dextromethorphan drug interactions

When used with monoamine oxidase inhibitors, it can cause high fever, coma, and even death.

Dextromethorphan drug evaluation

According to domestic reports, Beijing Friendship Hospital applied this product to 35 patients with acute and chronic bronchitis and pleural lesions with cough as the main symptom. It was administered orally at 10 mg each time 3 times a day for 1 week. Results After treatment, 5 cases were improved, 28 cases were markedly effective, 2 cases were ineffective, the effective rate was 94.4%; and 35 cases in the control group were oral clopispin (keping), 20 mg each time, 3 times a day, the effective rate was 77%. There were differences between the two groups (P <0.05). Another report compares the antitussive effect of dextromethorphan and pentovirin. The effective rate of observation of 300 patients was 95.3%. Only a few cases showed mild adverse reactions (1 case of dry mouth, 1 case of dizziness). , Stomach upset and nausea (1 case). It has been reported that 1 case of male abused dextromethorphan powder, inhaled 2 to 3 times a day for 2 to 3 months, and euphoria appeared after 15 minutes to 2 hours after inhaling the drug. However, the patient had no special symptoms after stopping the drug, only the feeling of craving for the drug. Dextromethorphan hydrobromide is widely used in clinical practice, with an effective rate of about 70%. It is a non-narcotic antitussive, has no analgesic effect, and is not addictive. The antitussive effect on moderate and severe cough is significantly stronger than that of cough, non-addictive, safe and reliable, and small adverse reactions, suitable for dry cough caused by various reasons. The use of nasal drops to treat patients with respiratory disease whose main manifestation is dry cough has shown good clinical efficacy. Antitussive for different levels of cough is always effective. The significant feature of dextromethorphan hydrobromide nasal drops is that the onset time of antitussive is significantly shorter than that of the compound dextromethorphan granules we have observed (25 ± 22) h. The adverse reactions of dextromethorphan hydrobromide are slight, with occasional dizziness, headache, drowsiness, constipation, and lack of appetite. The local irritation of the throat is generally tolerated by patients. ^[3]

Related news of dextromethorphan

FDA to assess dextromethorphan safety

May 04, 2010

Fearing the safety of the cold medicine dextromethorphan, the US Food and Drug Administration announced on the 3rd that it will convene external experts to evaluate its advantages and disadvantages.

The US Drug Administration issued a statement on the same day, saying that many young people in the United States have "sniffed" cold medicines containing dextromethorphan because this ingredient can make them feel psychedelic. The US Drug Control Agency has asked the Department of Health and Human Services to make a medical and scientific assessment of dextromethorphan. Therefore, the United States Drug Administration, affiliated with the Department of Health and Human Services, decided to hold an expert meeting open to the public on September 14, 2010 to assess the safety of dextromethorphan.

Dextromethorphan is included in more than 100 over-the-counter medicines sold in the United States. According to the American Consumer Healthcare Products Association, dextromethorphan is a safe and effective ingredient. However, the group called for legislation to ban the sale of products containing dextromethorphan to people under the age of 18.

Dextromethorphan has a central antitussive effect. If a drug containing this ingredient is taken in large doses, it may cause side effects such as brain damage, loss of consciousness and arrhythmia to consumers. Children have died in the United States after taking dextromethorphan capsules. ^[4]