What is Amitriptyline?
N, N-dimethyl-3- [1o, 11-dihydro-5H-dibenzo [a, d] cycloheptatriene-5-ylidene] -1-propylamine
- Amitriptyline is used to treat various types of depression or depression. It has a good effect on endogenous depression and menopausal depression, and it is also effective on the depressive state of reactive depression and neurosis. For patients with both anxiety and depression symptoms, the effect is better than that of imipramine. Combined with electrical shock for major depression, it can reduce the number of electrical shocks. Used to relieve chronic pain. It is also used to treat pediatric enuresis and ADHD.
- Drug name
- Amitriptyline
- Drug type
- Essential medicines
- English name
- Amitriptyline
- Chinese alias
- Amitriptyline; Ilavir; Ammetrigine
- English alias
- Amitid Elavil; Tryptizol; Amitril
Amitriptyline chemical name
- N, N-dimethyl-3- [1o, 11-dihydro-5H-dibenzo [a, d] cycloheptatriene-5-ylidene] -1-propylamine
Amitriptyline molecular structure
Amitriptyline molecular formula
- C20H23N
Amitriptyline molecular weight
- 277
Amitriptyline physical and chemical properties
- Its hydrochloride is commonly used as colorless crystals or white, off-white powder; odorless or almost odorless, bitter, with burning sensation, and then numbness. Soluble in water, methanol, ethanol or chloroform, almost insoluble in ether. Melting point is 195 to 199 ° C.
Amitriptyline Pharmacology
- This product is commonly used in clinical TCA, and its antidepressant effect is very similar to that of imipramine. Compared with the latter, this product has a stronger inhibitory effect on 5-HT reuptake than a NA reuptake; Choline effect is also more obvious. It can improve the mood of depression patients, and can improve symptoms such as slow thinking, slow behavior and loss of appetite. This product can also relieve chronic pain by acting on central opioid receptors. 7 to 10 days after drug administration can produce significant effects. Oral absorption is complete, peak plasma concentration reaches 8 to 12 cubits, plasma half-life is 32 to 40 hours, and protein binding rate is 82% to 96%. CYP2C19, 1A2, 2D6 are all metabolized by the liver, and the main metabolite is nortriptyline, which is still active. This product and metabolites are distributed throughout the body, can be excreted from milk through the placental barrier, and the final metabolites are excreted from the kidneys. Excretion is slow, and can still be detected in urine after 3 weeks of withdrawal.
Amitriptyline indications
- Used to treat various types of depression or depression. It has a good effect on endogenous depression and menopausal depression, and it is also effective on the depressive state of reactive depression and neurosis. For patients with both anxiety and depression symptoms, the effect is better than that of imipramine. Combined with electrical shock for major depression, it can reduce the number of electrical shocks. Used to relieve chronic pain. It is also used to treat pediatric enuresis and ADHD.
Amitriptyline usage and dosage
- Due to different dosage forms and specifications, please read the drug instructions carefully or follow the doctor's advice.
Amitriptyline adverse reactions
- Less and lighter than imipramine. Dry mouth, drowsiness, constipation, blurred vision, difficulty urinating, and palpitations are common. Occasionally arrhythmia, dizziness, dyskinesia, epileptic seizures, orthostatic hypotension, liver injury and tardive dyskinesia. There have been reports of occasional exacerbations of diabetes.
Amitriptyline contraindications
- Severe heart disease, glaucoma, benign prostatic hyperplasia with dysuria, paralytic intestinal obstruction, myasthenia gravis, hyperthyroidism, history of epilepsy, and use of MA0Is are prohibited.
Amitriptyline precautions
- See imipramine. Patients with severe liver and kidney dysfunction and bronchial asthma should be used with caution.
Amitriptyline drug interactions
- Combined with MA0Is to enhance the adverse reactions of this product. Combined with central nervous system inhibitory drugs, the effect of combined drugs is enhanced. Combination with adrenaline receptor agonists can cause severe hypertension and high fever. Combined with guanethidine to antagonize the hypotensive effect of guanethidine. Combined with thyroxine and phenothiazine, the effect of this product is enhanced. Clozapine and ofenafil can enhance the anticholinergic effect of this product.
Amitriptyline
- Tablet: 25mg
Amitriptyline Pharmacopeia Introduction
- [Identification] (1) Take about 5mg of this product, add 2ml of sulfuric acid to dissolve, the solution is red. (2) Take this product, add hydrochloric acid solution (9 1000), dissolve and dilute it to make a solution contained in each ml, and measure according to ultraviolet-visible spectrophotometry (Appendix VA). It has a maximum absorption at 239nm and absorbance It is 0.51-0.56. (3) The infrared absorption spectrum of this product should be consistent with the control spectrum (spectrum set 360). (4) Identification of chlorides in aqueous solution of this product (Appendix III). [Check] The acidity is 0.10g of this product. After adding 10ml of water to dissolve, determine it according to law (Appendix VI H). The pH value should be 4.5 ~ 6.0. The clarity and color of the solution is 0.20g of this product. After adding 10ml of water to dissolve, the solution should be clear and colorless. If the color is developed, it must not be deeper than the standard colorimetric solution No. 2 or Orange No. 2 (Appendix A, first method). Relevant substances: take this product, add mobile phase to dissolve and dilute to make a solution containing 0.2mg per lml, and use it as a test solution; take a precise amount and dilute it with mobile phase to make a solution containing 2µg per lml, as Control solution. According to the high performance liquid chromatography (Appendix VD) test, octadecylsilane bonded silica gel was used as the filler; methanol-water-triethylamine (60: 40: 0.3) (pH adjusted to 3.1 with phosphoric acid) was Mobile phase; detection wavelength is 240nm. The theoretical plate number is calculated to be not less than 3000 based on the amitriptyline hydrochloride peak. Take 10µl of the control 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 20% of the full range; then accurately measure 10µl each of the test solution and the control solution, and inject them into the liquid chromatograph , Record the chromatogram to the main component peak retention time 4 times. If there are impurity peaks in the chromatogram of the test solution, the area of a single impurity peak must not be greater than 0.5 times (0.5%) the area of the main peak of the control solution, and the sum of the area of each impurity peak must not be greater than the area of the main peak of the control solution (1.0%). Residual solvents: toluene, tetrahydrofuran and isopropanol. Take an appropriate amount of this product, accurately weigh it, add dimethylformamide to dissolve and dilute it to make a solution containing about 20mg per 1ml as the test solution; take toluene, tetrahydrofuran and Isopropanol, precisely weighed, was diluted with dimethylformamide to make a mixed solution containing about 17.8 µg of toluene in 1 ml; tetrahydrofuran 14.4 µg and 100 µg of isopropanol as a reference solution. According to the residual solvent determination method (Appendix P third method) test, 6% cyanopropylphenyl-94% dimethylpolysiloxane (or similar polarity) was used as the fixing solution, and the initial column temperature was 80 ° C. , Maintain for 10 minutes, heat up to 200 ° C at a rate of 20 ° C per minute, and maintain for 5 minutes; the inlet temperature is 250 ° C; the detector temperature is 2 50 ° C. Take 1µ1 of the reference solution and inject it into the gas chromatograph, and the resolution between the peaks of each component should meet the requirements; then accurately measure 1µ1 of each of the test solution and the reference solution, and inject them into the gas chromatograph, record the chromatogram, and follow the external standard The method is based on the peak area and should meet the requirements. Loss on drying Take this product, use phosphorus pentoxide as a desiccant, and dry under reduced pressure to constant weight at 60 ° C, and the weight loss should not exceed 0.5% (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 item of burning residue, and shall be inspected in accordance with law (Appendix 1 H second method). The heavy metal shall not exceed 15 parts per million. [Content determination] Take about 0.3g of this product, accurately weigh, add 10ml glacial acetic acid and 20ml acetic anhydride to dissolve, according to potentiometric titration (Appendix A), titrate with perchloric acid titration solution (0.1mol / L) And correct the titration results with a blank test. Each 1ml of perchloric acid titration solution (0.1mol / L) is equivalent to 31.39mg of C20H23NHCl. [Category] Antidepressants. [Storage] shading and sealed.