Astomin (Dimemorfan Phosphate Tablets) is a non-narcotic central antitussive. Since its launch in Japan in 1975, it has been widely used to relieve cough symptoms in adults due to its low side effects and low abuse risk. Like all medications, it may be accompanied by adverse reactions and medication risks while exerting therapeutic effects.

What Are the Side Effects of Astomin (Dimemorfan Phosphate Tablets)?

Allergic Reactions

Some patients may experience skin rashes. The incidence rate is unclear, but close observation of skin changes is required in the early stage of medication.

Psychoneurological Reactions

Dizziness and drowsiness: Common central inhibitory effects that may affect the ability to drive or operate precision machinery.

Headache or heavy head sensation: Mostly transient, usually alleviating gradually with prolonged medication.

Fatigue and lassitude: May be related to the drug’s regulatory effect on nerve function.

Gastrointestinal Discomfort

Dry mouth and loss of appetite: Caused by the drug’s inhibition of glandular secretion; small sips of water frequently are recommended for relief.

Nausea, vomiting, and diarrhea: Mostly occur in the early stage of medication, usually mild and self-resolving.

Severe Side Effects of Astomin (Dimemorfan Phosphate Tablets)

Risk of Aggravated Allergic Reactions

If a rash progresses to urticaria, difficulty breathing, or mucosal edema, vigilance should be maintained for the possibility of anaphylactic shock, and immediate medical intervention is necessary.

Severe Neurological Abnormalities

Persistent drowsiness, confusion, or motor coordination disorders may indicate excessive central nervous system depression, requiring dosage adjustment or medication replacement.

Acute Cardiovascular Symptoms

If palpitations are accompanied by chest pain, syncope, or significant blood pressure fluctuations, the drug’s impact on the cardiac conduction system should be evaluated.

Precautions for Using Astomin (Dimemorfan Phosphate Tablets)

Standardized Administration Methods

PTP Packaging Warning: Tablets must be removed from the aluminum foil blister before taking. Accidental ingestion of the aluminum foil may cause its sharp edges to pierce the esophageal mucosa, leading to life-threatening complications such as perforation and mediastinitis.

Individualized Dosage: For adults (over 15 years old), the recommended dosage is 1–2 tablets (equivalent to 10–20mg dimemorfan phosphate) per dose, three times a day. Dosage should be adjusted according to age and severity of symptoms.

Medication Restrictions for Special Populations

Pregnant and lactating women: Use only when therapeutic benefits outweigh risks. Lactating women need to weigh discontinuing the drug or suspending breastfeeding.

Elderly patients: Due to age-related decline in physiological functions, dose reduction and monitoring of adverse reactions are required.

Children and patients with hepatic or renal insufficiency: Relevant data are not clearly stated in the current package insert; the necessity of use should be fully evaluated before administration.

Storage and Expiry Date Management

The medication should be stored at room temperature, avoiding moisture and direct sunlight.

The expiry date is 36 months; expired medications are strictly prohibited for use.