In postmarketing experience, fatal outcomes have been reported for acute overdoses, primarily with mixed overdoses, but also with duloxetine only, at doses as low as 1000 mg. Signs and symptoms of overdose (duloxetine alone or with mixed drugs) included somnolence, coma, serotonin syndrome, seizures, syncope, tachycardia, hypotension, hypertension, and vomiting.
Management Of OverdoseThere is no specific antidote to CYMBALTA, but if serotonin syndrome ensues, specific treatment (such as with cyproheptadine and/or temperature control) may be considered. In case of acute overdose, treatment should consist of those general measures employed in the management of overdose with any drug.
An adequate airway, oxygenation, and ventilation should be assured, and cardiac rhythm and vital signs should be monitored. Induction of emesis is not recommended. Gastric lavage with a large-bore orogastric tube with appropriate airway protection, if needed, may be indicated if performed soon after ingestion or in symptomatic patients.
Activated charcoal may be useful in limiting absorption of duloxetine from the gastrointestinal tract. Administration of activated charcoal has been shown to decrease AUC and Cmax by an average of one-third, although some subjects had a limited effect of activated charcoal. Due to the large volume of distribution of this drug, forced diuresis, dialysis, hemoperfusion, and exchange transfusion are unlikely to be beneficial.
In managing overdose, the possibility of multiple drug involvement should be considered. A specific caution involves patients who are taking or have recently taken CYMBALTA and might ingest excessive quantities of a TCA. In such a case, decreased clearance of the parent tricyclic and/or its active metabolite may increase the possibility of clinically significant sequelae and extend the time needed for close medical observation. The physician should consider contacting a poison control center (1-800-222-1222 or www.poison.org) for additional information on the treatment of any overdose. Telephone numbers for certified poison control centers are listed in the Physicians’ Desk Reference (PDR).
The following serious adverse reactions are described below and elsewhere in the labeling:
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
The stated frequencies of adverse reactions represent the proportion of individuals who experienced, at least once, a treatment-emergent adverse reaction of the type listed. A reaction was considered treatment-emergent if it occurred for the first time or worsened while receiving therapy following baseline evaluation. Reactions reported during the studies were not necessarily caused by the therapy, and the frequencies do not reflect investigator impression (assessment) of causality.
AdultsThe data described below reflect exposure to CYMBALTA in placebo-controlled trials for MDD (N=3779), GAD (N=1018), OA (N=503), CLBP (N=600), DPNP (N=906), and FM (N=1294). The population studied was 17 to 89 years of age; 65.7%, 60.8%, 60.6%, 42.9%, and 94.4% female; and 81.8%, 72.6%, 85.3%, 74.0%, and 85.7% Caucasian for MDD, GAD, OA and CLBP, DPNP, and FM, respectively. Most patients received doses of a total of 60 to 120 mg per day.The data below do not include results of the trial examining the efficacy of CYMBALTA in patients ≥ 65 years old for the treatment of generalized anxiety disorder; however, the adverse reactions observed in this geriatric sample were generally similar to adverse reactions in the overall adult population.
Children And AdolescentsThe data described below reflect exposure to CYMBALTA in pediatric, 10-week, placebo-controlled trials for MDD (N=341) and GAD (N=135). The population studied (N=476) was 7 to 17 years of age with 42.4% children age 7 to 11 years of age, 50.6% female, and 68.6% white. Patients received 30-120 mg per day during placebo-controlled acute treatment studies. Additional data come from the overall total of 822 pediatric patients (age 7 to 17 years of age) with 41.7% children age 7 to 11 years of age and 51.8% female exposed to CYMBALTA in MDD and GAD clinical trials up to 36-weeks in length, in which most patients received 30-120 mg per day.
Adverse Reactions Reported As Reasons For Discontinuation Of Treatment In Adult Placebo-Controlled Trials Major Depressive DisorderApproximately 8.4% (319/3779) of the patients who received CYMBALTA in placebo-controlled trials for MDD discontinued treatment due to an adverse reaction, compared with 4.6% (117/2536) of the patients receiving placebo. Nausea (CYMBALTA 1.1%, placebo 0.4%) was the only common adverse reaction reported as a reason for discontinuation and considered to be drug-related (i.e., discontinuation occurring in at least 1% of the CYMBALTA-treated patients and at a rate of at least twice that of placebo).
Generalized Anxiety DisorderApproximately 13.7% (139/1018) of the patients who received CYMBALTA in placebo-controlled trials for GAD discontinued treatment due to an adverse reaction, compared with 5.0% (38/767) for placebo. Common adverse reactions reported as a reason for discontinuation and considered to be drug-related (as defined above) included nausea (CYMBALTA 3.3%, placebo 0.4%), and dizziness (CYMBALTA 1.3%, placebo 0.4%).
Diabetic Peripheral Neuropathic PainApproximately 12.9% (117/906) of the patients who received CYMBALTA in placebo-controlled trials for DPNP discontinued treatment due to an adverse reaction, compared with 5.1% (23/448) for placebo. Common adverse reactions reported as a reason for discontinuation and considered to be drug-related (as defined above) included nausea (CYMBALTA 3.5%, placebo 0.7%), dizziness (CYMBALTA 1.2%, placebo 0.4%), and somnolence (CYMBALTA 1.1%, placebo 0.0%).
FibromyalgiaApproximately 17.5% (227/1294) of the patients who received CYMBALTA in 3 to 6 month placebo-controlled trials for FM discontinued treatment due to an adverse reaction, compared with 10.1% (96/955) for placebo. Common adverse reactions reported as a reason for discontinuation and considered to be drug-related (as defined above) included nausea (CYMBALTA 2.0%, placebo 0.5%), headache (CYMBALTA 1.2%, placebo 0.3%), somnolence (CYMBALTA 1.1%, placebo 0.0%), and fatigue (CYMBALTA 1.1%, placebo 0.1%).
Chronic Pain due To OsteoarthritisApproximately 15.7% (79/503) of the patients who received CYMBALTA in 13-week, placebo-controlled trials for chronic pain due to OA discontinued treatment due to an adverse reaction, compared with 7.3% (37/508) for placebo. Common adverse reactions reported as a reason for discontinuation and considered to be drug-related (as defined above) included nausea (CYMBALTA 2.2%, placebo 1.0%).
Chronic Low Back PainApproximately 16.5% (99/600) of the patients who received CYMBALTA in 13-week, placebo-controlled trials for CLBP discontinued treatment due to an adverse reaction, compared with 6.3% (28/441) for placebo. Common adverse reactions reported as a reason for discontinuation and considered to be drug-related (as defined above) included nausea (CYMBALTA 3.0%, placebo 0.7%), and somnolence (CYMBALTA 1.0%, placebo 0.0%).
Most Common Adult Adverse Reactions Pooled Trials For All Approved IndicationsThe most commonly observed adverse reactions in CYMBALTA-treated patients (incidence of at least 5% and at least twice the incidence in placebo patients) were nausea, dry mouth, somnolence, constipation, decreased appetite, and hyperhidrosis.
Diabetic Peripheral Neuropathic PainThe most commonly observed adverse reactions in CYMBALTA-treated patients (as defined above) were nausea, somnolence, decreased appetite, constipation, hyperhidrosis, and dry mouth.
FibromyalgiaThe most commonly observed adverse reactions in CYMBALTA-treated patients (as defined above) were nausea, dry mouth, constipation, somnolence, decreased appetite, hyperhidrosis, and agitation.
Chronic Pain Due To OsteoarthritisThe most commonly observed adverse reactions in CYMBALTA-treated patients (as defined above) were nausea, fatigue, constipation, dry mouth, insomnia, somnolence, and dizziness.
Chronic Low Back PainThe most commonly observed adverse reactions in CYMBALTA-treated patients (as defined above) were nausea, dry mouth, insomnia, somnolence, constipation, dizziness, and fatigue.
Adverse Reactions Occurring At An Incidence Of 5% Or More Among CYMBALTA-Treated Patients In Adult Placebo-Controlled TrialsTable 2 gives the incidence of treatment-emergent adverse reactions in placebo-controlled trials for approved indications that occurred in 5% or more of patients treated with CYMBALTA and with an incidence greater than placebo.
Table 2: Treatment-Emergent Adverse Reactions: Incidence of 5% or More and Greater than Placebo in Placebo-Controlled Trials of Approved Indicationsa
| Adverse Reaction | Percentage of Patients Reporting Reaction | |
| CYMBALTA (N=8100) |
Placebo (N=5655) |
|
| Nauseac | 23 | 8 |
| Headache | 14 | 12 |
| Dry mouth | 13 | 5 |
| Somnolencee | 10 | 3 |
| Fatigueb,c | 9 | 5 |
| Insomniad | 9 | 5 |
| Constipationc | 9 | 4 |
| Dizzinessc | 9 | 5 |
| Diarrhea | 9 | 6 |
| Decreased appetitec | 7 | 2 |
| Hyperhidrosisc | 6 | 1 |
| Abdominal painf | 5 | 4 |
| a The inclusion of an event in the table is determined based on the percentages before rounding; however, the percentages displayed in the table are rounded to the nearest integer. b Also includes asthenia. c Events for which there was a significant dose-dependent relationship in fixed-dose studies, excluding three MDD studies which did not have a placebo lead-in period or dose titration. d Also includes initial insomnia, middle insomnia, and early morning awakening. e Also includes hypersomnia and sedation. f Also includes abdominal discomfort, abdominal pain lower, abdominal pain upper, abdominal tenderness, and gastrointestinal pain. |
Table 3 gives the incidence of treatment-emergent adverse reactions in MDD and GAD placebo-controlled trials for approved indications that occurred in 2% or more of patients treated with CYMBALTA and with an incidence greater than placebo.
Table 3: Treatment-Emergent Adverse Reactions: Incidence of 2% or More and Greater than Placebo in MDD and GAD Placebo-Controlled Trialsa,b
| System Organ Class / Adverse Reaction |
Percentage of Patients Reporting Reaction | |
| CYMBALTA (N=4797) |
Placebo (N=3303) |
|
| Cardiac Disorders | ||
| Palpitations | 2 | 1 |
| Eye Disorders | ||
| Vision blurred | 3 | 1 |
| Gastrointestinal Disorders | ||
| Nauseac | 23 | 8 |
| Dry mouth | 14 | 6 |
| Constipationc | 9 | 4 |
| Diarrhea | 9 | 6 |
| Abdominal paind | 5 | 4 |
| Vomiting | 4 | 2 |
| General Disorders and Administration Site Conditions | ||
| Fatiguee | 9 | 5 |
| Metabolism and Nutrition Disorders | ||
| Decreased appetitec | 6 | 2 |
| Nervous System Disorders | ||
| Headache | 14 | 14 |
| Dizzinessc | 9 | 5 |
| Somnolencef | 9 | 3 |
| Tremor | 3 | 1 |
| Psychiatric Disorders | ||
| Insomniag | 9 | 5 |
| Agitationh | 4 | 2 |
| Anxiety | 3 | 2 |
| Reproductive System and Breast Disorders | ||
| Erectile dysfunction | 4 | 1 |
| Ejaculation delayedc | 2 | 1 |
| Libido decreasedi | 3 | 1 |
| Orgasm abnormalj | 2 | <1 |
| Respiratory, Thoracic, and Mediastinal Disorders | ||
| Yawning | 2 | <1 |
| Skin and Subcutaneous Tissue Disorders | ||
| Hyperhidrosis | 6 | 2 |
| a The inclusion of an event in the table is determined based on the percentages before rounding; however, the percentages displayed in the table are rounded to the nearest integer. c For GAD, there were no adverse events that were significantly different between treatments in adults ≥65 years that were also not significant in the adults <65 years. c Events for which there was a significant dose-dependent relationship in fixed-dose studies, excluding three MDD studies which did not have a placebo lead-in period or dose titration. d Also includes abdominal pain upper, abdominal pain lower, abdominal tenderness, abdominal discomfort, and gastrointestinal pain e Also includes asthenia f Also includes hypersomnia and sedation g Also includes initial insomnia, middle insomnia, and early morning awakening h Also includes feeling jittery, nervousness, restlessness, tension and psychomotor hyperactivity i Also includes loss of libido j Also includes anorgasmia |
||
Table 4 gives the incidence of treatment-emergent adverse events that occurred in 2% or more of patients treated with CYMBALTA (determined prior to rounding) in the premarketing acute phase of DPNP, FM, OA, and CLBP placebo-controlled trials and with an incidence greater than placebo.
Table 4: Treatment-Emergent Adverse Reactions: Incidence of 2% or More and Greater than Placebo in DPNP,
FM, OA, and CLBP Placebo-Controlled Trialsa
| System Organ Class / Adverse Reaction |
Percentage of Patients Reporting Reaction | |
| CYMBALTA (N=3303) |
Placebo (N=2352) |
|
| Gastrointestinal Disorders | ||
| Nausea | 23 | 7 |
| Dry Mouthb | 11 | 3 |
| Constipationb | 10 | 3 |
| Diarrhea | 9 | 5 |
| Abdominal Painc | 5 | 4 |
| Vomiting | 3 | 2 |
| Dyspepsia | 2 | 1 |
| General Disorders and Administration Site Conditions | ||
| Fatigued | 11 | 5 |
| Infections and Infestations | ||
| Nasopharyngitis | 4 | 4 |
| Upper Respiratory Tract Infection | 3 | 3 |
| Influenza | 2 | 2 |
| Metabolism and Nutrition Disorders | ||
| Decreased Appetiteb | 8 | 1 |
| Musculoskeletal and Connective Tissue | ||
| Musculoskeletal Paine | 3 | 3 |
| Muscle Spasms | 2 | 2 |
| Nervous System Disorders | ||
| Headache | 13 | 8 |
| Somnolenceb,f | 11 | 3 |
| Dizziness | 9 | 5 |
| Paraesthesiag | 2 | 2 |
| Tremorb | 2 | <1 |
| Psychiatric Disorders | ||
| Insomniab,h | 10 | 5 |
| Agitationi | 3 | 1 |
| Reproductive System and Breast Disorders | ||
| Erectile Dysfunctionb | 4 | <1 |
| Ejaculation Disorderj | 2 | <1 |
| Respiratory, Thoracic, and Mediastinal Disorders | ||
| Cough | 2 | 2 |
| Skin and Subcutaneous Tissue Disorders | ||
| Hyperhidrosis | 6 | 1 |
| Vascular Disorders | ||
| Flushingk | 3 | 1 |
| Blood pressure increasedl | 2 | 1 |
| a The inclusion of an event in the table is determined based on the percentages before rounding; however, the percentages displayed in the table are rounded to the nearest integer. b Incidence of 120 mg/day is significantly greater than the incidence for 60 mg/day. c Also includes abdominal discomfort, abdominal pain lower, abdominal pain upper, abdominal tenderness and gastrointestinal pain d Also includes asthenia e Also includes myalgia and neck pain f Also includes hypersomnia and sedation g Also includes hypoaesthesia, hypoaesthesia facial, genital hypoaesthesia and paraesthesia oral h Also includes initial insomnia, middle insomnia, and early morning awakening. i Also includes feeling jittery, nervousness, restlessness, tension and psychomotor hyperactivity j Also includes ejaculation failure k Also includes hot flush l Also includes blood pressure diastolic increased, blood pressure systolic increased, diastolic hypertension, essential hypertension, hypertension, hypertensive crisis, labile hypertension, orthostatic hypertension, secondary hypertension, and systolic hypertension |
||
Changes in sexual desire, sexual performance and sexual satisfaction often occur as manifestations of psychiatric disorders or diabetes, but they may also be a consequence of pharmacologic treatment. Because adverse sexual reactions are presumed to be voluntarily underreported, the Arizona Sexual Experience Scale (ASEX), a validated measure designed to identify sexual side effects, was used prospectively in 4 MDD placebo-controlled trials. In these trials, as shown in Table 5 below, patients treated with CYMBALTA experienced significantly more sexual dysfunction, as measured by the total score on the ASEX, than did patients treated with placebo. Gender analysis showed that this difference occurred only in males. Males treated with CYMBALTA experienced more difficulty with ability to reach orgasm (ASEX Item 4) than males treated with placebo. Females did not experience more sexual dysfunction on CYMBALTA than on placebo as measured by ASEX total score. Negative numbers signify an improvement from a baseline level of dysfunction, which is commonly seen in depressed patients. Physicians should routinely inquire about possible sexual side effects.
Table 5: Mean Change in ASEX Scores by Gender in MDD Placebo-Controlled Trials
| Male Patientsa | Female Patientsa | |||
| CYMBALTA (n=175) |
Placebo (n=83) |
CYMBALTA (n=241) |
Placebo (n=126) |
|
| ASEX Total (Items 1-5) | 0.56b | -1.07 | -1.15 | -1.07 |
| Item 1 — Sex drive | -0.07 | -0.12 | -0.32 | -0.24 |
| Item 2 — Arousal | 0.01 | -0.26 | -0.21 | -0.18 |
| Item 3 — Ability to achieve erection (men); Lubrication (women) | 0.03 | -0.25 | -0.17 | -0.18 |
| Item 4 — Ease of reaching orgasm | 0.40c | -0.24 | -0.09 | -0.13 |
| Item 5 — Orgasm satisfaction | 0.09 | -0.13 | -0.11 | -0.17 |
| a n=Number of patients with non-missing change score for ASEX total b p=0.013 versus placebo c p<0.001 versus placebo |
In placebo-controlled clinical trials across approved indications for change from baseline to endpoint, CYMBALTA treatment was associated with mean increases of 0.23 mm Hg in systolic blood pressure and 0.73 mm Hg in diastolic blood pressure compared to mean decreases of 1.09 mm Hg systolic and 0.55 mm Hg diastolic in placebo-treated patients. There was no significant difference in the frequency of sustained (3 consecutive visits) elevated blood pressure.
CYMBALTA treatment, for up to 26 weeks in placebo-controlled trials across approved indications, typically caused a small increase in heart rate for change from baseline to endpoint compared to placebo of up to 1.37 beats per minute (increase of 1.20 beats per minute in CYMBALTA -treated patients, decrease of 0.17 beats per minute in placebo-treated patients).
Laboratory Changes In AdultsCYMBALTA treatment in placebo-controlled clinical trials across approved indications, was associated with small mean increases from baseline to endpoint in ALT, AST, CPK, and alkaline phosphatase; infrequent, modest, transient, abnormal values were observed for these analytes in CYMBALTA-treated patients when compared with placebo-treated patients. High bicarbonate, cholesterol, and abnormal (high or low) potassium, were observed more frequently in CYMBALTA treated patients compared to placebo.
Electrocardiogram Changes In AdultsThe effect of CYMBALTA 160 mg and 200 mg administered twice daily to steady state was evaluated in a randomized, double-blinded, two-way crossover study in 117 healthy female subjects. No QT interval prolongation was detected. CYMBALTA appears to be associated with concentration-dependent but not clinically meaningful QT shortening.
Other Adverse Reactions Observed During The Premarketing And Postmarketing Clinical Trial Evaluation Of CYMBALTA In AdultsFollowing is a list of treatment-emergent adverse reactions reported by patients treated with CYMBALTA in clinical trials. In clinical trials of all indications, 34,756 patients were treated with CYMBALTA. Of these, 26.9% (9337) took CYMBALTA for at least 6 months, and 12.4% (4317) for at least one year. The following listing is not intended to include reactions (1) already listed in previous tables or elsewhere in labeling, (2) for which a drug cause was remote, (3) which were so general as to be uninformative, (4) which were not considered to have significant clinical implications, or (5) which occurred at a rate equal to or less than placebo.
Reactions are categorized by body system according to the following definitions: frequent adverse reactions are those occurring in at least 1/100 patients; infrequent adverse reactions are those occurring in 1/100 to 1/1000 patients; rare reactions are those occurring in fewer than 1/1000 patients.
Cardiac Disorders — Frequent: palpitations; Infrequent: myocardial infarction and tachycardia.
Ear and Labyrinth Disorders — Frequent: vertigo; Infrequent: ear pain and tinnitus.
Endocrine Disorders — Infrequent: hypothyroidism.
Eye Disorders — Frequent: vision blurred; Infrequent: diplopia, dry eye, and visual impairment.
Gastrointestinal Disorders — Frequent: flatulence; Infrequent: dysphagia, eructation, gastritis, gastrointestinal hemorrhage, halitosis, and stomatitis; Rare: gastric ulcer.
General Disorders and Administration Site Conditions — Frequent: chills/rigors; Infrequent: falls, feeling abnormal, feeling hot and/or cold, malaise, and thirst; Rare: gait disturbance.
Infections and Infestations — Infrequent: gastroenteritis and laryngitis.
Investigations — Frequent: weight increased, weight decreased; Infrequent: blood cholesterol increased.
Metabolism and Nutrition Disorders — Infrequent: dehydration and hyperlipidemia; Rare: dyslipidemia.
Musculoskeletal and Connective Tissue Disorders — Frequent: musculoskeletal pain; Infrequent: muscle tightness and muscle twitching.
Nervous System Disorders — Frequent: dysgeusia, lethargy, and paraesthesia/hypoesthesia; Infrequent: disturbance in attention, dyskinesia, myoclonus, and poor quality sleep; Rare: dysarthria.
Psychiatric Disorders — Frequent: abnormal dreams and sleep disorder; Infrequent: apathy, bruxism, disorientation/confusional state, irritability, mood swings, and suicide attempt; Rare: completed suicide.
Renal and Urinary Disorders — Frequent: urinary frequency; Infrequent: dysuria, micturition urgency, nocturia, polyuria, and urine odor abnormal.
Reproductive System and Breast Disorders — Frequent: anorgasmia/orgasm abnormal; Infrequent: menopausal symptoms, sexual dysfunction, and testicular pain; Rare: menstrual disorder.
Respiratory, Thoracic and Mediastinal Disorders — Frequent: yawning, oropharyngeal pain; Infrequent: throat tightness.
Skin and Subcutaneous Tissue Disorders — Frequent: pruritus; Infrequent: cold sweat, dermatitis contact, erythema, increased tendency to bruise, night sweats, and photosensitivity reaction; Rare: ecchymosis.
Vascular Disorders — Frequent: hot flush; Infrequent: flushing, orthostatic hypotension, and peripheral coldness.
Adverse Reactions Observed In Children And Adolescent Placebo-Controlled Clinical TrialsThe adverse drug reaction profile observed in pediatric clinical trials (children and adolescents) was consistent with the adverse drug reaction profile observed in adult clinical trials. The specific adverse drug reactions observed in adult patients can be expected to be observed in pediatric patients (children and adolescents). The most common (≥5% and twice placebo) adverse reactions observed in pediatric clinical trials include: nausea, diarrhea, decreased weight, and dizziness.
Table 6 provides the incidence of treatment-emergent adverse reactions in MDD and GAD pediatric placebo-controlled trials that occurred in greater than 2% of patients treated with CYMBALTA and with an incidence greater than placebo.
Table 6: Treatment-Emergent Adverse Reactions: Incidence of 2% or More and Greater than Placebo in three 10week Pediatric Placebo-Controlled Trialsa
| System Organ Class/ Adverse Reaction |
Percentage of Pediatric Patients Reporting Reaction | |
| CYMBALTA (N=476) |
Placebo (N=362) |
|
| Gastrointestinal Disorders | ||
| Nausea | 18 | 8 |
| Abdominal Painb | 13 | 10 |
| Vomiting | 9 | 4 |
| Diarrhea | 6 | 3 |
| Dry Mouth | 2 | 1 |
| General Disorders and Administration Site Conditions | ||
| Fatiguec | 7 | 5 |
| Investigations | ||
| Decreased Weightd | 14 | 6 |
| Metabolism and Nutrition Disorders | ||
| Decreased Appetite | 10 | 5 |
| Nervous System Disorders | ||
| Headache | 18 | 13 |
| Somnolencee | 11 | 6 |
| Dizziness | 8 | 4 |
| Psychiatric Disorders | ||
| Insomniaf | 7 | 4 |
| Respiratory, Thoracic, and Mediastinal Disorders | ||
| Oropharyngeal Pain | 4 | 2 |
| Cough | 3 | 1 |
| a The inclusion of an event in the table is determined based on the percentages before rounding; however, the
percentages displayed in the table are rounded to the nearest integer. b Also includes abdominal pain upper, abdominal pain lower, abdominal tenderness, abdominal discomfort, and gastrointestinal pain. c Also includes asthenia. d Frequency based on weight measurement meeting potentially clinically significant threshold of ≥3.5% weight loss (N=467 CYMBALTA; N=354 Placebo). e Also includes hypersomnia and sedation. f Also includes initial insomnia, insomnia, middle insomnia, and terminal insomnia. |
||
Other adverse reactions that occurred at an incidence of less than 2% but were reported by more CYMBALTA treated patients than placebo treated patients and are associated CYMBALTA treatment: abnormal dreams (including ni
Preclinical studies have shown that duloxetine is a potent inhibitor of neuronal serotonin and norepinephrine reuptake and a less potent inhibitor of dopamine reuptake. Duloxetine has no significant affinity for dopaminergic, adrenergic, cholinergic, histaminergic, opioid, glutamate, and GABA receptors in vitro. Duloxetine does not inhibit monoamine oxidase (MAO).
CYMBALTA is in a class of drugs known to affect urethral resistance. If symptoms of urinary hesitation develop during treatment with CYMBALTA, consideration should be given to the possibility that they might be drug-related.
Duloxetine has an elimination half-life of about 12 hours (range 8 to 17 hours) and its pharmacokinetics are dose proportional over the therapeutic range. Steady-state plasma concentrations are typically achieved after 3 days of dosing. Elimination of duloxetine is mainly through hepatic metabolism involving two P450 isozymes, CYP1A2 and CYP2D6.
Absorption And DistributionOrally administered duloxetine hydrochloride is well absorbed. There is a median 2 hour lag until absorption begins (Tlag), with maximal plasma concentrations (Cmax) of duloxetine occurring 6 hours post dose. Food does not affect the Cmax of duloxetine, but delays the time to reach peak concentration from 6 to 10 hours and it marginally decreases the extent of absorption (AUC) by about 10%. There is a 3 hour delay in absorption and a one-third increase in apparent clearance of duloxetine after an evening dose as compared to a morning dose.
The apparent volume of distribution averages about 1640 L. Duloxetine is highly bound (>90%) to proteins in human plasma, binding primarily to albumin and α1-acid glycoprotein. The interaction between duloxetine and other highly protein bound drugs has not been fully evaluated. Plasma protein binding of duloxetine is not affected by renal or hepatic impairment.
Metabolism And EliminationBiotransformation and disposition of duloxetine in humans have been determined following oral administration of 14C-labeled duloxetine. Duloxetine comprises about 3% of the total radiolabeled material in the plasma, indicating that it undergoes extensive metabolism to numerous metabolites. The major biotransformation pathways for duloxetine involve oxidation of the naphthyl ring followed by conjugation and further oxidation. Both CYP1A2 and CYP2D6 catalyze the oxidation of the naphthyl ring in vitro. Metabolites found in plasma include 4-hydroxy duloxetine glucuronide and 5-hydroxy, 6-methoxy duloxetine sulfate. Many additional metabolites have been identified in urine, some representing only minor pathways of elimination. Only trace (<1% of the dose) amounts of unchanged duloxetine are present in the urine. Most (about 70%) of the duloxetine dose appears in the urine as metabolites of duloxetine; about 20% is excreted in the feces. Duloxetine undergoes extensive metabolism, but the major circulating metabolites have not been shown to contribute significantly to the pharmacologic activity of duloxetine.
Children And Adolescents (Ages 7 To 17 Years)Duloxetine steady-state plasma concentration was comparable in children (7 to 12 years of age), adolescents (13 to 17 years of age) and adults. The average steady-state duloxetine concentration was approximately 30% lower in the pediatric population (children and adolescents) relative to the adults. The model-predicted duloxetine steady state plasma concentrations in children and adolescents were mostly within the concentration range observed in adult patients and did not exceed the concentration range in adults.
Pregnancy Exposure Registry
There is a pregnancy registry that monitors the pregnancy outcomes in women exposed to CYMBALTA during pregnancy. To enroll, contact the CYMBALTA Pregnancy Registry at 1-866-814-6975 or www.cymbaltapregnancyregistry.com.
Risk Summary
There are no adequate and well-controlled studies of CYMBALTA administration in pregnant women. In animal studies with duloxetine, fetal weights were decreased but there was no evidence of teratogenicity in pregnant rats and rabbits at oral doses administered during the period of organogenesis up to 4 and 7 times the maximum recommended human dose (MRHD) of 120 mg/day, respectively. When duloxetine was administered orally to pregnant rats throughout gestation and lactation, pup weights at birth and pup survival to 1 day postpartum were decreased at a dose 2 times the MRHD. At this dose, pup behaviors consistent with increased reactivity, such as increased startle response to noise and decreased habituation of locomotor activity were observed. Post-weaning growth was not adversely affected. CYMBALTA should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus.
Clinical ConsiderationsFetal/Neonatal Adverse Reaction
Neonates exposed during pregnancy to serotonin -norepinephrine reuptake inhibitors (SNRIs) or selective serotonin reuptake inhibitors (SSRIs) have developed complications requiring prolonged hospitalization, respiratory support, and tube feeding which can arise immediately upon delivery. Reported clinical findings have included respiratory distress, cyanosis, apnea, seizures, temperature instability, feeding difficulty, vomiting, hypoglycemia, hypotonia, hypertonia, hyperreflexia, tremor, jitteriness, irritability, and constant crying. These features are consistent with either a direct toxic effect of the SNRIs or SSRIs, or possibly, a drug discontinuation syndrome. It should be noted that, in some cases, the clinical picture is consistent with serotonin syndrome.
DataAnimal Data
In animal reproduction studies, duloxetine has been shown to have adverse effects on embryo/fetal and postnatal development.
When duloxetine was administered orally to pregnant rats and rabbits during the period of organogenesis, there was no evidence of teratogenicity at doses up to 45 mg/kg/day (4 times the maximum recommended human dose (MRHD) of 120 mg/day on a mg/m2 basis, in rat; 7 times the MRHD in rabbit). However, fetal weights were decreased at this dose, with a no-effect dose of 10 mg/kg/day approximately equal to the MRHD in rats; 2 times the MRHD in rabbits).
When duloxetine was administered orally to pregnant rats throughout gestation and lactation, the survival of pups to 1 day postpartum and pup body weights at birth and during the lactation period were decreased at a dose of 30 mg/kg/day (2 times the MRHD); the no-effect dose was 10 mg/kg/day. Furthermore, behaviors consistent with increased reactivity, such as increased startle response to noise and decreased habituation of locomotor activity, were observed in pups following maternal exposure to 30 mg/kg/day. Post-weaning growth and reproductive performance of the progeny were not affected adversely by maternal duloxetine treatment.
