Clinical data | |
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Pronunciation | /ˌæmɪˈtrɪptɪliːn/ [1] |
Trade names | Elavil, others |
AHFS/Drugs.com | Monograph |
MedlinePlus | a682388 |
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Routes of administration | Oral, intramuscular injection |
Drug class | Tricyclic antidepressant (TCA) |
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Pharmacokinetic data | |
Bioavailability | 45% [5] -53% [6] |
Protein binding | 96% [7] |
Metabolism | Liver (CYP2D6, CYP2C19, CYP3A4) [8] [6] [9] |
Metabolites | nortriptyline, (E)-10-hydroxynortriptyline |
Elimination half-life | 21 hours [5] |
Excretion | Urine: 12–80% after 48 hours; [10] feces: not studied |
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CompTox Dashboard (EPA) | |
ECHA InfoCard | 100.000.038 |
Chemical and physical data | |
Formula | C20H23N |
Molar mass | 277.411 g·mol−1 |
3D model (JSmol) | |
Melting point | 197.5 °C (387.5 °F) [11] |
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Amitriptyline, sold under the brand name Elavil among others, is a tricyclic antidepressant primarily used to treat major depressive disorder, and a variety of pain syndromes such as neuropathic pain, fibromyalgia, migraine and tension headaches. [12] Due to the frequency and prominence of side effects, amitriptyline is generally considered a second-line therapy for these indications. [13] [14] [15] [16]
The most common side effects are dry mouth, drowsiness, dizziness, constipation, and weight gain. Glaucoma, liver toxicity and abnormal heart rhythms are rare but serious side effects. Blood levels of amitriptyline vary significantly from one person to another, [17] and amitriptyline interacts with many other medications potentially aggravating its side effects.
Amitriptyline was discovered in the late 1950s by scientists at Merck and approved by the US Food and Drug Administration (FDA) in 1961. [18] It is on the World Health Organization's List of Essential Medicines. [19] It is available as a generic medication. [20] In 2022, it was the 87th most commonly prescribed medication in the United States, with more than 7 million prescriptions. [21] [22]
Amitriptyline is indicated for the treatment of major depressive disorder, neuropathic pain and for the prevention of migraine and chronic tension headache. It can be used for the treatment of nocturnal enuresis in children older than 6 after other treatments have failed. [12]
Amitriptyline is effective for depression, [23] but it is rarely used as a first-line antidepressant due to its higher toxicity in overdose and generally poorer tolerability. [24] It can be tried for depression as a second-line therapy, after the failure of other treatments. [13] For treatment-resistant adolescent depression [25] or for cancer-related depression [26] amitriptyline is no better than placebo; however, the number of treated patients in both studies was small. It is sometimes used for the treatment of depression in Parkinson's disease, [27] but supporting evidence for that is lacking. [28]
Amitriptyline alleviates painful diabetic neuropathy. It is recommended by a variety of guidelines as a first or second line treatment. [14] It is as effective for this indication as gabapentin or pregabalin but less well tolerated. [29] Amitriptyline is as effective at relieving pain as duloxetine. Combination treatment of amitriptyline and pregabalin offers additional pain relief for people whose pain is not adequately controlled with one medication, and is usually safe. [30] [31] Amitriptyline in certain formulations may also induce the level of sciatic-nerve blockade needed for local anesthesia therein. [32] Here, it has been demonstrated to be of superior potency to bupivacaine, a customary long-acting local anesthetic.
Low doses of amitriptyline moderately improve sleep disturbances and reduce pain and fatigue associated with fibromyalgia. [33] It is recommended for fibromyalgia accompanied by depression by Association of the Scientific Medical Societies in Germany [33] and as a second-line option for fibromyalgia, with exercise being the first line option, by European League Against Rheumatism. [15] Combinations of amitriptyline and fluoxetine or melatonin may reduce fibromyalgia pain better than either medication alone. [34]
There is some (low-quality) evidence that amitriptyline may reduce pain in cancer patients. It is recommended only as a second line therapy for non-chemotherapy-induced neuropathic or mixed neuropathic pain, if opioids did not provide the desired effect. [35]
Moderate evidence exists in favor of amitriptyline use for atypical facial pain. [36] Amitriptyline is ineffective for HIV-associated neuropathy. [29]
In multiple sclerosis it is frequently used to treat painful paresthesias in the arms and legs (e.g., burning sensations, pins and needles, stabbing pains) caused by damage to the pain regulating pathways of the brain and spinal cord. [37]
Amitriptyline is probably effective for the prevention of periodic migraine in adults. Amitriptyline is similar in efficacy to venlafaxine and topiramate but carries a higher burden of adverse effects than topiramate. [16] For many patients, even very small doses of amitriptyline are helpful, which may allow for minimization of side effects. [38] Amitriptyline is not significantly different from placebo when used for the prevention of migraine in children. [39]
Amitriptyline may reduce the frequency and duration of chronic tension headache, but it is associated with worse adverse effects than mirtazapine. Overall, amitriptyline is recommended for tension headache prophylaxis, along with lifestyle advice, which should include avoidance of analgesia and caffeine. [40]
Amitriptyline is effective for the treatment of irritable bowel syndrome; however, because of its side effects, it should be reserved for select patients for whom other agents do not work. [41] [42] [43] There is insufficient evidence to support its use for abdominal pain in children with functional gastrointestinal disorders. [44]
Tricyclic antidepressants decrease the frequency, severity, and duration of cyclic vomiting syndrome episodes. Amitriptyline, as the most commonly used of them, is recommended as a first-line agent for its therapy. [45]
Amitriptyline may improve pain and urgency intensity associated with bladder pain syndrome and can be used in the management of this syndrome. [46] [47] Amitriptyline can be used in the treatment of nocturnal enuresis in children. However, its effect is not sustained after the treatment ends. Alarm therapy gives better short- and long-term results. [48]
In the US, amitriptyline is commonly used in children with ADHD as an adjunct to stimulant medications without any evidence or guideline supporting this practice. [49] Many physicians in the UK (and the US also) commonly prescribe amitriptyline for insomnia; [50] however, Cochrane reviewers were not able to find any randomized controlled studies that would support or refute this practice. [51] Similarly, a major systematic review and network meta-analysis of medications for the treatment of insomnia published in 2022 found little evidence to inform the use of amitriptyline for insomnia. [52] The well-known sedating effects of amitriptyline, however, bear understanding on and arguable justification for this practice. It may function similarly to doxepin in this regard, although the evidence for doxepin is more robust. [53] Trimipramine may be a more novel alternative given its tendency to not suppress but brighten R.E.M. sleep. [54] [55] [56]
The known contraindications of amitriptyline are: [12]
Amitriptyline should be used with caution in patients with epilepsy, impaired liver function, pheochromocytoma, urinary retention, prostate enlargement, hyperthyroidism, and pyloric stenosis. [12]
In patients with the rare condition of shallow anterior chamber of eyeball and narrow anterior chamber angle, amitriptyline may provoke attacks of acute glaucoma due to dilation of the pupil. It may aggravate psychosis, if used for depression with schizophrenia, or precipitate the switch to mania in those with bipolar disorder. [12]
CYP2D6 poor metabolizers should avoid amitriptyline due to increased side effects. If it is necessary to use it, half dose is recommended. [57] Amitriptyline can be used during pregnancy and lactation when SSRIs have been shown not to work. [58]
The most frequent side effects, occurring in 20% or more of users, are dry mouth, drowsiness, dizziness, constipation, and weight gain (on average 1.8 kg [59] ). [23] Other common side effects are headache problems (amblyopia, blurred vision), tachycardia, increased appetite, tremor, fatigue/asthenia/feeling slowed down, and dyspepsia. [23]
A less common side effect of amitriptyline is urination problems (8.7%). [23]
Amitriptyline can increase suicidal thoughts and behavior in people under the age of 24 and the US FDA required a boxed warning to be added to the prescription label.. [60] [61] Amitriptyline-associated sexual dysfunction (occurring at a frequency of 6.9%) seems to be mostly confined to males with depression and is expressed predominantly as erectile dysfunction and low libido disorder, with lesser frequency of ejaculatory and orgasmic problems. The rate of sexual dysfunction in males treated for indications other than depression and in females is not significantly different from placebo. [62]
Liver test abnormalities occur in 10–12% of patients on amitriptyline, but are usually mild, asymptomatic and transient, [63] with consistently elevated alanine transaminase in 3% of all patients. [64] [65] The increases of the enzymes above the 3-fold threshold of liver toxicity are uncommon, and cases of clinically apparent liver toxicity are rare; [63] nevertheless, amitriptyline is placed in the group of antidepressants with greater risks of hepatic toxicity. [64]
Amitriptyline prolongs the QT interval. [66] This prolongation is relatively small at therapeutic doses [67] but becomes severe in overdose. [68]
The symptoms and the treatment of an overdose are largely the same as for the other TCAs, including the presentation of serotonin syndrome and adverse cardiac effects. The British National Formulary notes that amitriptyline can be particularly dangerous in overdose, [69] thus it and other TCAs are no longer recommended as first-line therapy for depression. The treatment of overdose is mostly supportive as no specific antidote for amitriptyline overdose is available. Activated charcoal may reduce absorption if given within 1–2 hours of ingestion. If the affected person is unconscious or has an impaired gag reflex, a nasogastric tube may be used to deliver the activated charcoal into the stomach. ECG monitoring for cardiac conduction abnormalities is essential and if one is found close monitoring of cardiac function is advised. Body temperature should be regulated with measures such as heating blankets if necessary. Cardiac monitoring is advised for at least five days after the overdose. Benzodiazepines are recommended to control seizures. Dialysis is of no use due to the high degree of protein binding with amitriptyline. [7]
Since amitriptyline and its active metabolite nortriptyline are primarily metabolized by cytochromes CYP2D6 and CYP2C19 (see Amitriptyline#Pharmacology), the inhibitors of these enzymes are expected to exhibit pharmacokinetic interactions with amitriptyline. According to the prescribing information, the interaction with CYP2D6 inhibitors may increase the plasma level of amitriptyline. [12] However, the results in the other literature are inconsistent: [8] the co-administration of amitriptyline with a potent CYP2D6 inhibitor paroxetine does increase the plasma levels of amitriptyline two-fold and of the main active metabolite nortriptyline 1.5-fold, [70] but combination with less potent CYP2D6 inhibitors thioridazine or levomepromazine does not affect the levels of amitriptyline and increases nortriptyline by about 1.5-fold; [71] a moderate CYP2D6 inhibitor fluoxetine does not seem to have a significant effect on the levels of amitriptyline or nortriptyline. [72] [73] A case of clinically significant interaction with potent CYP2D6 inhibitor terbinafine has been reported. [74]
A potent inhibitor of CYP2C19 and other cytochromes fluvoxamine increases the level of amitriptyline two-fold while slightly decreasing the level of nortriptyline. [72] Similar changes occur with a moderate inhibitor of CYP2C19 and other cytochromes cimetidine: amitriptyline level increases by about 70%, while nortriptyline decreases by 50%. [75] CYP3A4 inhibitor ketoconazole elevates amitriptyline level by about a quarter. [9] On the other hand, cytochrome P450 inducers such as carbamazepine and St. John's Wort decrease the levels of both amitriptyline and nortriptyline [71] [76]
Oral contraceptives may increase the blood level of amitriptyline by as high as 90%. [77] Valproate moderately increases the levels of amitriptyline and nortriptyline through an unclear mechanism. [78]
The prescribing information warns that the combination of amitriptyline with monoamine oxidase inhibitors may cause potentially lethal serotonin syndrome; [12] however, this has been disputed. [79] The prescribing information cautions that some patients may experience a large increase in amitriptyline concentration in the presence of topiramate. [60] However, other literature states that there is little or no interaction: in a pharmacokinetic study topiramate only increased the level of amitriptyline by 20% and nortriptyline by 33%. [80]
Amitriptyline counteracts the antihypertensive action of guanethidine. [7] [81] When given with amitriptyline, other anticholinergic agents may result in hyperpyrexia or paralytic ileus. [60] Co-administration of amitriptyline and disulfiram is not recommended due to the potential for the development of toxic delirium. [7] [82] Amitriptyline causes an unusual type of interaction with the anticoagulant phenprocoumon during which great fluctuations of the prothrombin time have been observed. [83]
Site | AMI | NTI | Species | Ref |
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SERT | 2.8–36 | 15–279 | Human | [85] [86] |
NET | 19–102 | 1.8–21 | Human | [85] [86] |
DAT | 3,250 | 1,140 | Human | [85] |
5-HT1A | 450–1,800 | 294 | Human | [87] [88] |
5-HT1B | 840 | ND | Rat | [89] |
5-HT2A | 18–23 | 41 | Human | [87] [88] |
5-HT2B | 174 | ND | Human | [90] |
5-HT2C | 4-8 | 8.5 | Rat | [91] [92] |
5-HT3 | 430 | 1,400 | Rat | [93] |
5-HT6 | 65–141 | 148 | Human/rat | [94] [95] [96] |
5-HT7 | 92.8–123 | ND | Rat | [97] |
α1A | 6.5–25 | 18–37 | Human | [98] [99] |
α1B | 600–1700 | 850–1300 | Human | [98] [99] |
α1D | 560 | 1500 | Human | [99] |
α2 | 114–690 | 2,030 | Human | [86] [87] |
α2A | 88 | ND | Human | [100] |
α2B | >1000 | ND | Human | [100] |
α2C | 120 | ND | Human | [100] |
β | >10,000 | >10,000 | Rat | [101] [92] |
D1 | 89 | 210 (rat) | Human/rat | [102] [92] |
D2 | 196–1,460 | 2,570 | Human | [87] [102] |
D3 | 206 | ND | Human | [102] |
D4 | ND | ND | ND | ND |
D5 | 170 | ND | Human | [102] |
H1 | 0.5–1.1 | 3.0–15 | Human | [102] [103] [104] |
H2 | 66 | 646 | Human | [103] |
H3 | 75,900;>1000 | 45,700 | Human | [102] [103] |
H4 | 34–26,300 | 6,920 | Human | [103] [105] |
M1 | 11.0–14.7 | 40 | Human | [106] [107] |
M2 | 11.8 | 110 | Human | [106] |
M3 | 12.8–39 | 50 | Human | [106] [107] |
M4 | 7.2 | 84 | Human | [106] |
M5 | 15.7–24 | 97 | Human | [106] [107] |
σ1 | 287–300 | 2,000 | Guinea pig/rat | [108] [109] |
hERG | 3,260 | 31,600 | Human | [110] [111] |
PARP1 | 1650 | ND | Human | [112] |
TrkA | 3,000 (agonist) | ND | Human | [113] |
TrkB | 14,000 (agonist) | ND | Human | [113] |
Values are Ki (nM), unless otherwise noted. The smaller the value, the more strongly the drug binds to the site. |
Amitriptyline inhibits serotonin transporter (SERT) and norepinephrine transporter (NET). It is metabolized to nortriptyline, a stronger norepinephrine reuptake inhibitor, further augmenting amitriptyline's effects on norepinephrine reuptake (see table in this section).
Amitriptyline additionally acts as a potent inhibitor of the serotonin 5-HT2A, 5-HT2C, the α1A-adrenergic, the histamine H1 and the M1-M5 muscarinic acetylcholine receptors (see table in this section).
Amitriptyline is a non-selective blocker of multiple ion channels, in particular, voltage-gated sodium channels Nav1.3, Nav1.5, Nav1.6, Nav1.7, and Nav1.8, [114] [115] [116] voltage-gated potassium channels Kv7.2/ Kv7.3, [117] Kv7.1, Kv7.1/KCNE1, [118] and hERG. [110]
Inhibition of serotonin and norepinephrine transporters by amitriptyline results in interference with neuronal reuptake of serotonin and norepinephrine. Since the reuptake process is important physiologically in terminating transmitting activity, this action may potentiate or prolong activity of serotonergic and adrenergic neurons and is believed to underlie the antidepressant activity of amitriptyline. [60]
Inhibition of norepinephrine reuptake leading to increased concentration of norepinephrine in the posterior gray column of the spinal cord appears to be mostly responsible for the analgesic action of amitriptyline. Increased level of norepinephrine increases the basal activity of alpha-2 adrenergic receptors, which mediate an analgesic effect by increasing gamma-aminobutyric acid transmission among spinal interneurons. The blocking effect of amitriptyline on sodium channels may also contribute to its efficacy in pain conditions. [6]
Amitriptyline is readily absorbed from the gastrointestinal tract (90–95%). [6] Absorption is gradual with the peak concentration in blood plasma reached after about 4 hours. [5] Extensive metabolism on the first pass through the liver leads to average bioavailability of about 50% (45% [5] -53% [6] ). Amitriptyline is metabolized mostly by CYP2C19 into nortriptyline and by CYP2D6 leading to a variety of hydroxylated metabolites, with the principal one among them being (E)-10-hydroxynortriptyline [8] (see metabolism scheme), [6] and to a lesser degree, by CYP3A4. [9]
Nortriptyline, the main active metabolite of amitriptyline, is an antidepressant on its own right. Nortriptyline reaches 10% higher level in the blood plasma than the parent drug amitriptyline and 40% greater area under the curve, and its action is an important part of the overall action of amitriptyline. [5] [8]
Another active metabolite is (E)-10-hydroxynortriptyline, which is a norepinephrine uptake inhibitor four times weaker than nortriptyline. (E)-10-hydroxynortiptyline blood level is comparable to that of nortriptyline, but its cerebrospinal fluid level, which is a close proxy of the brain concentration of a drug, is twice higher than nortriptyline's. Based on this, (E)-10-hydroxynortriptyline was suggested to significantly contribute to antidepressant effects of amitriptyline. [119]
Blood levels of amitriptyline and nortriptyline and pharmacokinetics of amitriptyline in general, with clearance difference of up to 10-fold, vary widely between individuals. [120] Variability of the area under the curve in steady state is also high, which makes a slow upward titration of the dose necessary. [17]
In the blood, amitriptyline is 96% bound to plasma proteins; nortriptyline is 93–95% bound, and (E)-10-hydroxynortiptyline is about 60% bound. [7] [121] [119] Amitriptyline has an elimination half life of 21 hours, [5] nortriptyline – 23–31 hours, [122] and (E)-10-hydroxynortiptyline − 8–10 hours. [119] Within 48 hours, 12−80% of amitriptyline is eliminated in the urine, mostly as metabolites. [10] 2% of the unchanged drug is excreted in the urine. [123] Elimination in the feces, apparently, have not been studied.
Therapeutic levels of amitriptyline range from 75 to 175 ng/mL (270–631 nM), [124] or 80–250 ng/mL of both amitriptyline and its metabolite nortriptyline. [125]
Since amitriptyline is primarily metabolized by CYP2D6 and CYP2C19, genetic variations within the genes coding for these enzymes can affect its metabolism, leading to changes in the concentrations of the drug in the body. [126] Increased concentrations of amitriptyline may increase the risk for side effects, including anticholinergic and nervous system adverse effects, while decreased concentrations may reduce the drug's efficacy. [127] [128] [129] [130]
Individuals can be categorized into different types of CYP2D6 or CYP2C19 metabolizers depending on which genetic variations they carry. These metabolizer types include poor, intermediate, extensive, and ultrarapid metabolizers. Most individuals (about 77–92%) are extensive metabolizers, [57] and have "normal" metabolism of amitriptyline. Poor and intermediate metabolizers have reduced metabolism of the drug as compared to extensive metabolizers; patients with these metabolizer types may have an increased probability of experiencing side effects. Ultrarapid metabolizers use amitriptyline much faster than extensive metabolizers; patients with this metabolizer type may have a greater chance of experiencing pharmacological failure. [127] [128] [57] [130]
The Clinical Pharmacogenetics Implementation Consortium recommends avoiding amitriptyline in patients who are CYP2D6 ultrarapid or poor metabolizers, due to the risk for a lack of efficacy and side effects, respectively. The consortium also recommends considering an alternative drug not metabolized by CYP2C19 in patients who are CYP2C19 ultrarapid metabolizers. A reduction in starting dose is recommended for patients who are CYP2D6 intermediate metabolizers and CYP2C19 poor metabolizers. If use of amitriptyline is warranted, therapeutic drug monitoring is recommended to guide dose adjustments. [57] The Dutch Pharmacogenetics Working Group also recommends selecting an alternative drug or monitoring plasma concentrations of amitriptyline in patients who are CYP2D6 poor or ultrarapid metabolizers, and selecting an alternative drug or reducing initial dose in patients who are CYP2D6 intermediate metabolizers. [131]
Amitriptyline is a highly lipophilic molecule having an octanol-water partition coefficient (pH 7.4) of 3.0, [132] while the log P of the free base was reported as 4.92. [133] Solubility of the free base amitriptyline in water is 14 mg/L. [134] Amitriptyline is prepared by reacting dibenzosuberane with 3-(dimethylamino)propylmagnesium chloride and then heating the resulting intermediate product with hydrochloric acid to eliminate water. [6]
Amitriptyline was first developed by the American pharmaceutical company Merck in the late 1950s. In 1958, Merck approached a number of clinical investigators proposing to conduct clinical trials of amitriptyline for schizophrenia. One of these researchers, Frank Ayd, instead, suggested using amitriptyline for depression. Ayd treated 130 patients and, in 1960, reported that amitriptyline had antidepressant properties similar to another, and the only known at the time, tricyclic antidepressant imipramine. [135] Following this, the US Food and Drug Administration approved amitriptyline for depression in 1961. [18]
In Europe, due to a quirk of the patent law at the time allowing patents only on the chemical synthesis but not on the drug itself, Roche and Lundbeck were able to independently develop and market amitriptyline in the early 1960s. [136]
According to research by an historian of psychopharmacology David Healy, amitriptyline became a much bigger selling drug than its precursor imipramine because of two factors. First, amitriptyline has much stronger anxiolytic effect. Second, Merck conducted a marketing campaign raising clinicians' awareness of depression as a clinical entity. [136] [135]
In the 2021 film The Many Saints of Newark , amitriptyline (referred to by the brand name Elavil) is part of the plot line of the movie. [137]
Amitriptyline is the English and French generic name of the drug and its INN , BAN , and DCF , while amitriptyline hydrochloride is its USAN , USP , BANM , and JAN . [138] [139] [140] [141] Its generic name in Spanish and Italian and its DCIT are amitriptilina, in German is Amitriptylin, and in Latin is amitriptylinum. [139] [141] The embonate salt is known as amitriptyline embonate, which is its BANM, or as amitriptyline pamoate unofficially. [139]
Between 1998 and 2017, along with imipramine, amitriptyline was the most commonly prescribed first antidepressant for children aged 5–11 years in England. It was also the most prescribed antidepressant (along with fluoxetine) for 12- to 17-year olds. [142]
The few randomized controlled trials investigating amitriptyline efficacy in eating disorder have been discouraging. [143]
Tricyclic antidepressants (TCAs) are a class of medications that are used primarily as antidepressants. TCAs were discovered in the early 1950s and were marketed later in the decade. They are named after their chemical structure, which contains three rings of atoms. Tetracyclic antidepressants (TeCAs), which contain four rings of atoms, are a closely related group of antidepressant compounds.
Sertraline, sold under the brand name Zoloft among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The effectiveness of sertraline for depression is similar to that of other antidepressants, and the differences are mostly confined to side effects. Sertraline is better tolerated than the older tricyclic antidepressants. Sertraline is effective for panic disorder, social anxiety disorder, generalized anxiety disorder (GAD), and obsessive–compulsive disorder (OCD). Although approved for post-traumatic stress disorder (PTSD), sertraline leads to only modest improvement in this condition. Sertraline also alleviates the symptoms of premenstrual dysphoric disorder (PMDD) and can be used in sub-therapeutic doses or intermittently for its treatment.
Fluvoxamine, sold under the brand name Luvox among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is primarily used to treat major depressive disorder and obsessive–compulsive disorder (OCD), but is also used to treat anxiety disorders such as panic disorder, social anxiety disorder, and post-traumatic stress disorder.
Maprotiline, sold under the brand name Ludiomil among others, is a tetracyclic antidepressant (TeCA) that is used in the treatment of depression. It may alternatively be classified as a tricyclic antidepressant (TCA), specifically a secondary amine. In terms of its chemistry and pharmacology, maprotiline is closely related to such-other secondary-amine TCAs as nortriptyline and protriptyline and has similar effects to them, albeit with more distinct anxiolytic effects. Additionally, whereas protriptyline tends to be somewhat more stimulating and in any case is distinctly more-or-less non-sedating, mild degrees of sedation may be experienced with maprotiline.
Mirtazapine, sold under the brand name Remeron among others, is an atypical tetracyclic antidepressant, and as such is used primarily to treat depression. Its effects may take up to four weeks but can also manifest as early as one to two weeks. It is often used in cases of depression complicated by anxiety or insomnia. The effectiveness of mirtazapine is comparable to other commonly prescribed antidepressants. It is taken by mouth.
Duloxetine, sold under the brand name Cymbalta among others, is a medication used to treat major depressive disorder, generalized anxiety disorder, obsessive-compulsive disorder, fibromyalgia, neuropathic pain and central sensitization. It is taken by mouth.
Atomoxetine, sold under the brand name Strattera, is a selective norepinephrine reuptake inhibitor medication used to treat attention deficit hyperactivity disorder (ADHD) and, to a lesser extent, cognitive disengagement syndrome. It may be used alone or along with psychostimulants. It enhances the executive functions of self-motivation, sustained attention, inhibition, working memory, reaction time and emotional self-regulation. Use of atomoxetine is only recommended for those who are at least six years old. It is taken orally. The effectiveness of atomoxetine is comparable to the commonly prescribed stimulant medication methylphenidate.
Cimetidine, sold under the brand name Tagamet among others, is a histamine H2 receptor antagonist that inhibits stomach acid production. It is mainly used in the treatment of heartburn and peptic ulcers.
Imipramine, sold under the brand name Tofranil, among others, is a tricyclic antidepressant (TCA) mainly used in the treatment of depression. It is also effective in treating anxiety and panic disorder. Imipramine is taken by mouth.
Clomipramine, sold under the brand name Anafranil among others, is a tricyclic antidepressant (TCA). It is used in the treatment of various conditions, most notably obsessive–compulsive disorder but also many other disorders, including hyperacusis, panic disorder, major depressive disorder, trichotillomania, body dysmorphic disorder and chronic pain. It has also been notably used to treat premature ejaculation and the cataplexy associated with narcolepsy.
Nortriptyline, sold under the brand name Aventyl, among others, is a tricyclic antidepressant. This medicine is also sometimes used for neuropathic pain, attention deficit hyperactivity disorder (ADHD), smoking cessation and anxiety. As with many antidepressants, its use for young people with depression and other psychiatric disorders may be limited due to increased suicidality in the 18–24 population initiating treatment. Nortriptyline is a less preferred treatment for ADHD and stopping smoking. It is taken by mouth.
Doxepin is a medication belonging to the tricyclic antidepressant (TCA) class of drugs used to treat major depressive disorder, anxiety disorders, chronic hives, and insomnia. For hives it is a less preferred alternative to antihistamines. It has a mild to moderate benefit for sleeping problems. It is used as a cream for itchiness due to atopic dermatitis or lichen simplex chronicus.
{{Distinguish|Dextrorphan|Dexamethasone}
Trimipramine, sold under the brand name Surmontil among others, is a tricyclic antidepressant (TCA) which is used to treat depression. It has also been used for its sedative, anxiolytic, and weak antipsychotic effects in the treatment of insomnia, anxiety disorders, and psychosis, respectively. The drug is described as an atypical or "second-generation" TCA because, unlike other TCAs, it seems to be a fairly weak monoamine reuptake inhibitor. Similarly to other TCAs, however, trimipramine does have antihistamine, antiserotonergic, antiadrenergic, antidopaminergic, and anticholinergic activities.
Trazodone, sold under many brand names, is an antidepressant medication, used to treat major depressive disorder, anxiety disorders, and insomnia. It is a phenylpiperazine compound of the serotonin antagonist and reuptake inhibitor (SARI) class. The medication is taken orally.
Cytochrome P450 2C19 is an enzyme protein. It is a member of the CYP2C subfamily of the cytochrome P450 mixed-function oxidase system. This subfamily includes enzymes that catalyze metabolism of xenobiotics, including some proton pump inhibitors and antiepileptic drugs. In humans, it is the CYP2C19 gene that encodes the CYP2C19 protein. CYP2C19 is a liver enzyme that acts on at least 10% of drugs in current clinical use, most notably the antiplatelet treatment clopidogrel (Plavix), drugs that treat pain associated with ulcers, such as omeprazole, antiseizure drugs such as mephenytoin, the antimalarial proguanil, and the anxiolytic diazepam.
Medifoxamine, previously sold under the brand names Clédial and Gerdaxyl, is an atypical antidepressant with additional anxiolytic properties acting via dopaminergic and serotonergic mechanisms which was formerly marketed in France and Spain, as well as Morocco. The drug was first introduced in France sometime around 1990. It was withdrawn from the market in 1999 (Morocco) and 2000 (France) following incidences of hepatotoxicity.
Amitriptylinoxide, or amitriptyline N-oxide, is a tricyclic antidepressant (TCA) which was introduced in Europe in the 1970s for the treatment of depression.
Vortioxetine, sold under the brand name Trintellix among others, is an antidepressant of the serotonin modulator and stimulator (SMS) class. Its effectiveness is viewed as similar to that of other antidepressants. It is taken orally.
The pharmacology of antidepressants is not entirely clear. The earliest and probably most widely accepted scientific theory of antidepressant action is the monoamine hypothesis, which states that depression is due to an imbalance of the monoamine neurotransmitters. It was originally proposed based on the observation that certain hydrazine anti-tuberculosis agents produce antidepressant effects, which was later linked to their inhibitory effects on monoamine oxidase, the enzyme that catalyses the breakdown of the monoamine neurotransmitters. All currently marketed antidepressants have the monoamine hypothesis as their theoretical basis, with the possible exception of agomelatine which acts on a dual melatonergic-serotonergic pathway. Despite the success of the monoamine hypothesis it has a number of limitations: for one, all monoaminergic antidepressants have a delayed onset of action of at least a week; and secondly, there are a sizeable portion (>40%) of depressed patients that do not adequately respond to monoaminergic antidepressants. Further evidence to the contrary of the monoamine hypothesis are the recent findings that a single intravenous infusion with ketamine, an antagonist of the NMDA receptor — a type of glutamate receptor — produces rapid, robust and sustained antidepressant effects. Monoamine precursor depletion also fails to alter mood. To overcome these flaws with the monoamine hypothesis a number of alternative hypotheses have been proposed, including the glutamate, neurogenic, epigenetic, cortisol hypersecretion and inflammatory hypotheses. Another hypothesis that has been proposed which would explain the delay is the hypothesis that monoamines don't directly influence mood, but influence emotional perception biases.
Livia is already troubled enough in the yesteryear of Many Saints that her doctor wants to prescribe her the antidepressant Elavil, but she rejects it. "I'm not a drug addict!" she sneers. Tony pores over the Elavil pamphlet with great interest and even schemes with Dickie Moltisanti to get his suffering mother to take it: "It could make her happy."