cyamemazine

Action and Spectrum

Actions and Spectrum: 

It involves a combination of dopamine receptor antagonism and antihistamine effects.  

• Dopamine Receptor Antagonism: Like other phenothiazines, cyamemazine primarily acts as a dopamine receptor antagonist. It blocks dopamine receptors in the brain, particularly the D2 receptors. This blockade reduces the effects of dopamine, a neurotransmitter that plays a role in various functions, including mood, emotion, and cognition. 
• Antihistamine Effects: cyamemazine also possesses antihistamine properties. Histamine is another neurotransmitter that plays a role in various physiological processes, including the sleep-wake cycle. By blocking histamine receptors, cyamemazine can contribute to sedation and may have antiemetic (anti-nausea) effects. 

Drug Interaction

Adverse Reaction

Frequency not defined 

Parkinsonian symptoms 

Akathisia 

GI disturbances 

Antimuscarinic symptoms 

ECG changes 

Blood dyscrasias 

Dystonia 

Tardive dyskinesia 

Nasal congestion 

CV symptoms 

Endocrine effects 

Photosensitization 

Black Box Warning

Black box warning: 

None 

Contraindication / Caution

Contraindications/caution: 

Contraindications: 

• Hypersensitivity or Allergy: This medication should not be used by individuals with a known hypersensitivity or allergy to cyamemazine or other phenothiazines. 
• Severe Central Nervous System Depression: cyamemazine can have sedative effects. Therefore, it is generally contraindicated in situations where central nervous system depression is severe, such as in comatose states. 
• Subcortical Brain Damage: The use of cyamemazine is generally contraindicated in individuals with subcortical brain damage, which may include conditions affecting the deeper brain structures. 
• Blood Dyscrasias: cyamemazine should be used with caution or avoided in individuals with blood dyscrasias, such as bone marrow depression, leukopenia, or agranulocytosis. 
• Pheochromocytoma: Individuals with pheochromocytoma, a tumor of the adrenal gland that can cause a release of excess catecholamines, may be at risk of hypertensive crisis when treated with cyamemazine. 

Caution: 

• Elderly Patients: Caution due to increased sensitivity and higher risk of adverse effects. 
• Cardiovascular Conditions: Monitor individuals with heart-related issues for potential orthostatic hypotension. 
• Renal Impairment: Caution in cases of severe kidney impairment due to potential effects on metabolite excretion. 
• Hepatic Impairment: Use with caution in individuals with severe liver dysfunction, as cyamemazine is metabolized in the liver. 

Pregnancy / Lactation

Pregnancy consideration: Insufficient data available 

Lactation: Excretion of the drug in human breast milk is unknown 

Pregnancy category: 

Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 

Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.    

Category X: Drugs listed in this category outweigh the risks over benefits. Hence, these categories of drugs need to be avoided by pregnant women.    

Category N: There is no data available for the drug under this category 

Pharmacology

Pharmacology: 

cyamemazine, an antipsychotic medication, exerts its effects through: 

• Dopamine Receptor Antagonism: Blocks dopamine receptors, especially D2 receptors, influencing neurotransmission associated with mood, emotion, and psychotic symptoms. 
• Histamine H1 Receptor Blockade: Exhibits potent antihistamine properties by blocking histamine H1 receptors, contributing to sedation and aiding in the management of agitation and anxiety in psychiatric disorders. 
• Alpha-Adrenergic Receptor Blockade: May display alpha-adrenergic receptor blocking, causing orthostatic hypotension (drop in blood pressure when standing) and contributing to sedative effects. 
• Muscarinic Receptor Blockade: Induces antimuscarinic effects by blocking muscarinic acetylcholine receptors, leading to side effects like dry mouth, blurred vision, constipation, and urinary retention. 

Pharmacokinetics: 

Absorption 

cyamemazine is administered orally. Its absorption occurs in the gastrointestinal tract after oral administration. The rate and extent of absorption can be influenced by factors such as the formulation of the drug and individual patient characteristics. 

Distribution 

Once absorbed, cyamemazine is distributed throughout the body. It crosses the blood-brain barrier, allowing it to exert its effects on the central nervous system. The drug may also be distributed to other tissues. 

Metabolism 

cyamemazine is metabolized primarily in the liver. The process involves enzymatic activity, with the cytochrome P450 enzyme system playing a role. Specific enzymes involved in the metabolism of cyamemazine include CYP1A2, CYP2D6, and CYP3A4. 

Elimination and Excretion 

cyamemazine’s metabolites are excreted from the body through urine and feces. The exact proportions of excretion through these routes may vary. 

Adminstartion

Administration: 

Oral administration 

• cyamemazine is mainly taken by mouth. 
• The tablets should be swallowed whole with water and not crushed or chewed unless directed otherwise by a healthcare professional. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: cyamemazine 

Why do we use cyamemazine? 

cyamemazine is primarily used as an antipsychotic medication with additional anxiolytic (anxiety-reducing) and soothing properties.  

• Treatment of Schizophrenia: cyamemazine is indicated for the treatment of schizophrenia, a severe mental disorder characterized by disturbances in thought processes, emotions, and perception of reality. It helps in managing symptoms such as hallucinations, delusions, and disorganized thinking. 
• Anxiolytic Effects: cyamemazine possesses anxiolytic properties, meaning it can help reduce symptoms of anxiety. This can be beneficial in the treatment of conditions where anxiety is a prominent feature, such as certain anxiety disorders. 
• Sedation and Agitation: The sedative effects of cyamemazine may be utilized to manage agitation and restlessness associated with psychiatric disorders. This can contribute to a calming effect in individuals with certain mental health conditions.