What Is Doxepin?
N, N-dimethyl-3-dibenzo [b, e] oxepin-11 (6H) subunit-1-propylamine
- Doxepin, is commonly used in the treatment of depression and various anxiety-depressive neurosis, and can also be used in menopausal psychosis. It is also effective for depression and anxiety and chronic alcoholic disorders. Can also be used for sedation and hypnosis. This product topical plaster is used to treat chronic simple lichen, eczema, allergic dermatitis, atopic dermatitis and so on.
- Drug name
- Docepin
- Drug type
- Essential medicines
- English name
- Doxepin
- Chinese alias
- Doxepin; Kaishu; Kaiser
- English alias
- Adapin; Aponal; Cidoxepin
Doxepin chemical name
- N, N-dimethyl-3-dibenzo [b, e] oxepin-11 (6H) subunit-1-propylamine
Doxepin molecular structure
Doxepin molecular formula
- C19H21N0
Doxepin molecular weight
- 279
Physical and chemical properties of docepin
- Its hydrochloride is commonly used. White powder, soluble in water, soluble in ethanol or chloroform, insoluble in benzene.
Doxepin pharmacology
- This drug is a dibenzopyrene compound, and it is one of the antidepressants with strong sedative function in TCAs. The mechanism of action is the same as that of amitriptyline and imipramine. It has the effect of inhibiting 5-HT reuptake, while the antidepressant effect is weaker than that of imipramine, it has a certain anxiolytic effect, and the anticholinergic effect is weak. This product also has a certain anti-histamine H1, H2 receptor effect, can be used to treat allergic skin diseases. It is easily absorbed by oral administration and reaches the peak of blood drug concentration in 2 to 4 hours. The half-life is 8-25 hours. The plasma protein binding rate was 76%. It is widely distributed in the body and can pass through the blood-brain barrier and placental barrier. It is metabolized in the liver through the first pass and is demethylated to produce the main metabolite nordocepine. Then doxepin and its metabolites are hydroxylated and N-oxidized by the liver, and the metabolites are excreted by the kidneys. This product can also be exuded through milk.
Doxepin indication
- It is often used in the treatment of depression and various anxiety-depressive neurosis. It can also be used for menopausal psychosis. It is also effective for depression and anxiety physical diseases and chronic alcoholic psychosis. Can also be used for sedation and hypnosis. This product topical plaster is used to treat chronic simple lichen, eczema, allergic dermatitis, atopic dermatitis and so on.
Doxepin usage and dosage
- Due to different dosage forms and specifications, please read the drug instructions carefully or follow the doctor's advice.
Doxepin adverse reactions
- Fewer adverse reactions. A small number of patients may have mild excitement, insomnia, dry mouth, constipation, blurred vision, etc. Some symptoms may disappear on their own during continued medication. Local topical application can also cause drowsiness and other systemic reactions. The most common local reactions are burning and acupuncture.
Doxepin contraindications
- Patients who are allergic to TCAs, severe liver dysfunction, glaucoma, myocardial infarction recovery period, hyperthyroidism, urinary retention, delirium, mania are prohibited.
Doxepin considerations
- Difficulty urinating, high intraocular pressure, heart disease, epilepsy, mild to moderate liver dysfunction, and renal dysfunction should be used with caution. Use with caution for pregnant women and children under 12 years of age. The topical application can only be applied to the undamaged skin and cannot be applied to the eyes and mucous membranes.
Doxepin drug interactions
- This product is forbidden to be used in combination with monoamine oxidase inhibitors (such as moclobemide, chlorogiline, selegiline, etc.), because it is prone to lethal 5-HT syndrome (high blood pressure, tachycardia, high fever, muscle, etc.) Clonics, excitatory changes in mental state, etc.). Combination with CYP2D6 inhibitors (such as quinidine, cimetidine, paroxetine, sertraline, fluoxetine, etc.) will increase the blood concentration of this product and prolong the elimination half-life. Combination with liver drug enzyme inducers (such as phenytoin, barbiturates, carbamazepine, etc.) will reduce the blood concentration of this product and accelerate the clearance rate. Combined with anticholinergic drugs or antihistamine drugs, it will produce atropine-like effects (such as dry mouth, dilated pupils, decreased bowel movements, etc.). Combination with coumarin drugs (such as warfarin) will reduce the metabolism of anticoagulants and increase the risk of bleeding. Combination with Nefopam, Tramadol and Iohexol will increase the risk of seizures. When combined with thyroxine preparations, it is easy to strengthen each other, cause arrhythmia, and even produce toxic reactions. Combined with pseudoadrenaline drugs, the boosting effect of combined drugs is enhanced.
Doxepin
- Tablet: 25mg
Doxepin Pharmacopeia Introduction
- [Identification] (1) Take this product, add 0.0lmol / L hydrochloric acid in methanol to dissolve and dilute it to make a solution containing 0.04mg per ml. Determine it according to ultraviolet-visible spectrophotometry (Appendix A), at a wavelength of 297nm. There is maximum absorption at 0.50 0.55. (2) The infrared absorption spectrum of this product should be consistent with the control spectrum (spectrum set 347). (3) Identification of chlorides in aqueous solution of this product (Appendix III). [Check] Take 0.10g of this product for acidity, dissolve it by adding 10ml of water, and measure it according to law (Appendix VI H). The pH value should be 4.5 6.5. Relevant substances are taken from this product, and the mobile phase is dissolved and diluted to make a solution containing 1.0 mg per 1 ml, which is used as the test solution; a precise amount is taken to 2 ml. Place in a 100ml volumetric flask, dilute to the mark with mobile phase, shake well, and accurately measure 5ml, place in a 50ml volumetric flask, dilute to the mark with mobile phase, shake well, and use as a control solution. According to the chromatographic conditions under the content determination item, take 20l of the reference solution, and inject it into the liquid chromatograph, adjust the detection sensitivity so that the peak height of the main component chromatographic peak is about 30% of the full range; accurately measure the test solution and the reference solution Each 20µl was injected into the liquid chromatograph, and the chromatogram was recorded to double the retention time of the main component peak. If there is an impurity peak in the chromatogram of the test solution, the area of a single impurity peak must not be greater than the sum of the two main peak areas of the cis-trans isomer of the control solution (0.2%), and the sum of the area of each impurity peak must not be greater than the cis-trans isomer of the control solution The area of the two main peaks is 2.5 times (0.5%). The proportion of isomers is determined according to the method of content determination, and the peak area is calculated according to the external standard method. The cis-isomer (Z) in the test product should be 17.0% to 23.0%. Loss on drying Take this product and dry to constant weight at 105 ° C. Loss of weight should not exceed 1.0% (Appendix L). Take 1.0g of this product and check it according to law (Appendix N). The remaining residue should not exceed 0.1%. The heavy metal shall be taken as the residue left under the burning residue, and shall be inspected according to law (Appendix VII H, second method). The content of heavy metal shall not exceed 20 parts per million. [Content determination] Determination according to high performance liquid chromatography (Appendix VD). Chromatographic conditions and system suitability test using octadecylsilane bonded silica gel as filler; 0.2mol / L sodium dihydrogen phosphate solution containing 0.1% triethylamine-methanol (65:35) (using 2mol / L phosphoric acid Adjust the pH value to 2.5) as the mobile phase; the detection wavelength is 254nm; the column temperature is 50 ° C. The theoretical plate number is calculated to be not less than 1500 according to the cis isomer (Z), and the resolution of the peaks of the trans isomer (E) and the cis isomer (Z) should meet the requirements. Take this product by assay, weigh it accurately, add mobile phase to dissolve and dilute it to make a solution containing about 0.1mg per lml, and accurately measure 20µl into the liquid chromatograph and record the chromatogram; take another doxepin hydrochloride control Product, the same method. According to the external standard method, the sum of the two peak areas of the trans isomer (E) and the cis isomer (Z) is calculated, which is obtained. [Category] Antidepressants. [Storage] shading and sealed.