The following adverse reactions are discussed in greater detail in other sections of the label.

• Hypersensitivity [see CONTRAINDICATIONS]
• Suicidal Thoughts and Behaviors in Adolescents and Young Adults [see WARNINGS AND PRECAUTIONS]
• Serotonin Syndrome [see WARNINGS AND PRECAUTIONS]
• Elevated Blood Pressure [see WARNINGS AND PRECAUTIONS]
• Abnormal Bleeding [see WARNINGS AND PRECAUTIONS]
• Narrow-Angle Glaucoma [see WARNINGS AND PRECAUTIONS]
• Activation of Mania/Hypomania [see WARNINGS AND PRECAUTIONS]
• Discontinuation Syndrome [see WARNINGS AND PRECAUTIONS]
• Seizure [see WARNINGS AND PRECAUTIONS]
• Hyponatremia [see WARNINGS AND PRECAUTIONS]
• Interstitial Lung Disease and Eosinophilic Pneumonia [see WARNINGS AND PRECAUTIONS]

Clinical Studies Experience

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 studies of another drug and may not reflect the rates observed in clinical practice.

Patient exposure

PRISTIQ was evaluated for safety in 4,158 patients diagnosed with major depressive disorder who participated in multiple-dose pre-marketing studies, representing 1,677 patient-years of exposure. Among these 4,158 PRISTIQ treated patients; 1,834 patients were exposed to PRISTIQ in 8-week, placebo-controlled studies at doses ranging from 50 to 400 mg/day. Out of the 1,834 patients, 687 PRISTIQ treated patients continued into a 10-month open-label study. Of the total 4,158 patients exposed to at least one dose of PRISTIQ; 1,320 were exposed to PRISTIQ for 6 months, representing 1058 patient-years of exposure, and 274 were exposed for one year, representing 241 patient-years of exposure.

Adverse reactions reported as reasons for discontinuation of treatment

In the pooled 8-week placebo-controlled studies in patients with MDD, 12% of the 1,834 patients who received PRISTIQ (50 to 400 mg) discontinued treatment due to an adverse reaction, compared with 3% of the 1,116 placebo-treated patients. At the recommended dose of 50 mg, the discontinuation rate due to an adverse reaction for PRISTIQ (4.1%) was similar to the rate for placebo (3.8%). For the 100 mg dose of PRISTIQ the discontinuation rate due to an adverse reaction was 8.7%.

The most common adverse reactions leading to discontinuation in at least 2% and at a rate greater than placebo of the PRISTIQ treated patients in the short-term studies, up to 8 weeks, were: nausea (4%); dizziness, headache and vomiting (2% each); in the longer-term studies, up to 11 months, the most common was vomiting (2%).

Common adverse reactions in placebo-controlled MDD studies

The most commonly observed adverse reactions in PRISTIQ treated MDD patients in short-term fixed-dose studies (incidence ≥ 5% and at least twice the rate of placebo in the 50 or 100 mg dose groups) were: nausea, dizziness, insomnia, hyperhidrosis, constipation, somnolence, decreased appetite, anxiety, and specific male sexual function disorders.

Table 2 shows the incidence of common adverse reactions that occurred in ≥ 2% of PRISTIQ treated MDD patients and twice the rate of placebo at any dose in the pooled 8-week, placebo-controlled, fixed dose clinical studies

Table 2: Common Adverse Reactions ( ≥ 2% in any Fixed-Dose Group and Twice the Rate of Placebo) in Pooled MDD 8-Week Placebo-Controlled Studies

Sexual function adverse reactions

Table 3 shows the incidence of sexual function adverse reactions that occurred in ≥ 2% of PRISTIQ treated MDD patients in any fixed-dose group (pooled 8-week, placebo-controlled, fixed and flexible-dose, clinical studies).

Table 3: Sexual Function Adverse Reactions ( ≥ 2% in Men or Women in any PRISTIQ Group) During the On-Therapy Period

Other adverse reactions observed in clinical studies

Other infrequent adverse reactions, not described elsewhere in the label, occurring at an incidence of < 2% in MDD patients treated with PRISTIQ were:

Cardiac disorders – tachycardia.

General disorders and administration site conditions – Asthenia

Investigations – Weight increased, liver function test abnormal, blood prolactin increased.

Musculoskeletal and connective tissue disorders – Musculoskeletal stiffness.

Nervous system disorders –Syncope, convulsion, dystonia.

Psychiatric disorders – Depersonalization, bruxism.

Renal and urinary disorders – Urinary retention.

Skin and subcutaneous tissue disorders – Rash, alopecia, photosensitivity reaction, angioedema.

In clinical studies, there were uncommon reports of ischemic cardiac adverse reactions, including myocardial ischemia, myocardial infarction, and coronary occlusion requiring revascularization; these patients had multiple underlying cardiac risk factors. More patients experienced these events during PRISTIQ treatment as compared to placebo.

Laboratory, ECG and vital sign changes observed in MDD clinical studies

The following changes were observed in placebo-controlled, short-term MDD studies with PRISTIQ.

Lipids

Elevations in fasting serum total cholesterol, LDL (low density lipoproteins) cholesterol, and triglycerides occurred in the controlled studies. Some of these abnormalities were considered potentially clinically significant.

The percentage of patients who exceeded a predetermined threshold value is shown in Table 4.

Table 4: Incidence (%) of Patients With Lipid Abnormalities of Potential Clinical Significance*

Proteinuria

Proteinuria, greater than or equal to trace, was observed in the fixed-dose controlled studies (see Table 5). This proteinuria was not associated with increases in BUN or creatinine and was generally transient.

Table 5: Incidence (%) of Patients with Proteinuria in the Fixed-dose Clinical Studies

Vital sign changes

Table 6 summarizes the changes that were observed in placebo-controlled, short-term, pre-marketing studies with PRISTIQ in patients with MDD (doses 50 to 400 mg).

Table 6: Mean Changes in Vital Signs at Final on Therapy for All Short-term, Fixed-dose Controlled Studies

Treatment with PRISTIQ at all doses from 50 mg/day to 400 mg/day in controlled studies was associated with sustained hypertension, defined as treatment-emergent supine diastolic blood pressure (SDBP) ≥ 90 mm Hg and ≥ 10 mm Hg above baseline for 3 consecutive on-therapy visits (see Table 7). Analyses of patients in PRISTIQ short-term controlled studies who met criteria for sustained hypertension revealed a consistent increase in the proportion of patients who developed sustained hypertension. This was seen at all doses with a suggestion of a higher rate at 400 mg/day.

Table 7: Proportion of Patients with Sustained Elevation of Supine Diastolic Blood Pressure

Orthostatic hypotension

In the short-term, placebo-controlled clinical studies with doses of 50 to 400 mg, systolic orthostatic hypotension (decrease ≥ 30 mm Hg from supine to standing position) occurred more frequently in patients ≥ 65 years of age receiving PRISTIQ (8%, 7/87) versus placebo (2.5%, 1/40), compared to patients < 65 years of age receiving PRISTIQ (0.9%, 18/1,937) versus placebo (0.7%, 8/1,218).

Postmarketing Experience

The following adverse reaction has been identified during post-approval use of PRISTIQ. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure:

Skin and subcutaneous tissue disorders – Stevens-Johnson syndrome.

Read the Pristiq (desvenlafaxine extended-release tablets) Side Effects Center for a complete guide to possible side effects »

Monoamine Oxidase Inhibitors (MAOI)

[see DOSAGE AND ADMINISTRATION, CONTRAINDICATIONS and WARNINGS AND PRECAUTIONS]

Serotonergic Drugs

[see DOSAGE AND ADMINISTRATION, CONTRAINDICATIONS and WARNINGS AND PRECAUTIONS]

Drugs that Interfere with Hemostasis (e.g., NSAIDs, Aspirin, and Warfarin)

Serotonin release by platelets plays an important role in hemostasis. Epidemiological studies of case-control and cohort design that have demonstrated an association between use of psychotropic drugs that interfere with serotonin reuptake and the occurrence of upper gastrointestinal bleeding. These studies have also shown that concurrent use of an NSAID or aspirin may potentiate this risk of bleeding. Altered anticoagulant effects, including increased bleeding, have been reported when SSRIs and SNRIs are co-administered with warfarin. Patients receiving warfarin therapy should be carefully monitored when PRISTIQ is initiated or discontinued [see WARNINGS AND PRECAUTIONS].

Potential for Desvenlafaxine to Affect Other Drugs

Clinical studies have shown that desvenlafaxine does not have a clinically relevant effect on CYP2D6 metabolism at the dose of 100 mg daily. Substrates primarily metabolized by CYP2D6 (e.g., desipramine , atomoxetine, dextromethorphan, metoprolol, nebivolol, perphenazine, tolterodine) should be dosed at the original level when co-administered with PRISTIQ 100 mg or lower. Reduce the dose of these substrates by one-half if co-administered with 400 mg of PRISTIQ. The substrate dose should be increased to the original level when 400 mg of PRISTIQ is discontinued.

Other Drugs Containing Desvenlafaxine or Venlafaxine

Avoid use of PRISTIQ with other desvenlafaxine-containing products or venlafaxine products. The concomitant use of PRISTIQ with other desvenlafaxine-containing products or venlafaxine will increase desvenlafaxine blood levels and increase dose-related adverse reactions [see ADVERSE REACTIONS].

Ethanol

A clinical study has shown that PRISTIQ does not increase the impairment of mental and motor skills caused by ethanol. However, as with all CNS-active drugs, patients should be advised to avoid alcohol consumption while taking PRISTIQ.

Drug Abuse And Dependence

Controlled Substance

PRISTIQ is not a controlled substance.

Last reviewed on RxList: 3/6/2013
This monograph has been modified to include the generic and brand name in many instances.