Dimemorfan Phosphate Tablets (Astomin) are a type of non-narcotic central antitussive. Since its first approval in Japan in 1975, it has been widely used to relieve cough symptoms in adults due to its low side effects and low risk of abuse.
What Are the Precautions for Taking Dimemorfan Phosphate Tablets (Astomin)?
Dosage Form and Administration Specifications
Dimemorfan Phosphate Tablets are white sugar-coated tablets and must be swallowed whole.
It is particularly important to note that if the medication is packaged in PTP (Press-Through Package) aluminum foil, patients must be instructed to remove the tablets from the aluminum foil before taking them.
Accidental ingestion of aluminum foil may lead to severe complications such as esophageal mucosal perforation or mediastinitis, so clear warnings must be given when dispensing the medication.
Dosage and Target Population
Dosage for adults: For patients aged 15 years and above, take 1–2 tablets (equivalent to 10–20 mg of dimemorfan phosphate) orally each time, three times a day. The dosage should be adjusted according to the patient’s age and symptoms.
Special populations: Pregnant and lactating women need to weigh the therapeutic benefits against risks and use the medication only when the benefits are clear. Data on the use of this medication in patients with renal or hepatic impairment is not yet clear, so careful evaluation is required.
Prevention of Adverse Reactions
Common adverse reactions include skin rashes, dizziness, drowsiness, dry mouth, and nausea.
Before administering the medication, it is necessary to inquire about the patient’s allergy history. If a skin rash occurs, the medication must be discontinued immediately.
If fatigue or dizziness occurs after taking the medication, the patient should avoid driving or operating machinery.
A very small number of patients may experience palpitations or facial flushing, so cardiovascular reactions need to be monitored.
Medication Monitoring for Dimemorfan Phosphate Tablets (Astomin)
Efficacy and Tolerability Assessment
Cough symptom monitoring: Record changes in the frequency and severity of cough after medication administration to evaluate the antitussive effect. If symptoms do not improve within 3 days, re-diagnosis or treatment plan adjustment is required.
Observation of central nervous system reactions: Pay attention to whether the patient experiences drowsiness or weakness, especially in elderly patients, for whom regular cognitive function checks are necessary.
Safety Indicator Tracking
Allergic and skin reactions: Closely observe for signs such as skin rashes after the first dose. Although the incidence rate is not clear, this item must be a key monitoring focus.
Digestive system and metabolism: Patients taking the medication for a long time need regular liver and kidney function tests. Although the package insert does not specify related impairments, based on its metabolic characteristics (approximately 60% excretion rate in urine), potential cumulative risks must be guarded against.
Dynamic Management of Special Populations
Elderly patients: Evaluate physiological functions in each treatment course and prioritize the use of the minimum effective dose.
Pregnant and lactating women: Document the basis for medication decisions and monitor fetal development or infant feeding status.


