What the label lists and what reports show
Venlafaxine side effects
Venlafaxine's FDA label: “Most common adverse reactions (incidence ≥5% and at least twice the rate of placebo): nausea, somnolence, dry mouth, sweating, abnormal ejaculation, anorexia, constipation, impotence (men), and libido decreased ( 6.1 ).” FAERS holds 131,560 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is nausea (9,125 reports).
- Generic listed
- Boxed warning
Check it at the source: the venlafaxine FDA label on DailyMed (effective August 15, 2023, Viatris Specialty LLC); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of EFFEXOR XR?EFFEXOR XR may cause serious side effects, including: • See “What is the most important information I should know about EFFEXOR XR?” • Serotonin syndrome. Taking EFFEXOR XR can cause a potentially life-threatening problem called serotonin syndrome. The risk of developing serotonin syndrome is increased when EFFEXOR XR is taken with certain other medicines. […]
Source: FDA drug label, NDA020699 (Upjohn), as published by Viatris Specialty LLC, effective August 15, 2023 (SPL set c848a5d8-ba94-4c84-80e3-0bf35fb8e32e), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse reactions (incidence ≥5% and at least twice the rate of placebo): nausea, somnolence, dry mouth, sweating, abnormal ejaculation, anorexia, constipation, impotence (men), and libido decreased ( 6.1 ).
Table 9: Common Adverse Reactions: Percentage of Patients Reporting Adverse Reactions (≥2% and > placebo) in Placebo-controlled Studies (up to 12 Weeks Duration) across All Indications
| Body System Adverse Reaction | Effexor XR n = 3,558 | Placebo n = 2,197 |
|---|---|---|
| Asthenia | 12.6 | 7.8 |
| Hypertension | 3.4 | 2.6 |
| Palpitation | 2.2 | 2.0 |
| Vasodilatation | 3.7 | 1.9 |
| Anorexia | 9.8 | 2.6 |
| Constipation | 9.3 | 3.4 |
| Diarrhea | 7.7 | 7.2 |
| Dry mouth | 14.8 | 5.3 |
| Nausea | 30.0 | 11.8 |
| Vomiting | 4.3 | 2.7 |
| Abnormal dreams | 2.9 | 1.4 |
| Dizziness | 15.8 | 9.5 |
| Insomnia | 17.8 | 9.5 |
| Libido decreased | 5.1 | 1.6 |
| Nervousness | 7.1 | 5.0 |
| Paresthesia | 2.4 | 1.4 |
| Somnolence | 15.3 | 7.5 |
| Tremor | 4.7 | 1.6 |
| Yawn | 3.7 | 0.2 |
| Sweating (including night sweats) | 11.4 | 2.9 |
| Abnormal vision | 4.2 | 1.6 |
| Abnormal ejaculation/orgasm (men) Percentages based on the number of men (Effexor XR, n =… | 9.9 | 0.5 |
| Anorgasmia (men) | 3.6 | 0.1 |
| Anorgasmia (women) Percentages based on the number of women (Effexor XR, n = 2,118;… | 2.0 | 0.2 |
| Impotence (men) | 5.3 | 1.0 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following adverse reactions are discussed in more detail in other sections of the labeling: • Hypersensitivity [see Contraindications (4) ] • Suicidal Thoughts and Behaviors in Adolescents and Young Adults [see Warnings and Precautions (5.1) ] • Serotonin Syndrome [see Warnings and Precautions (5.2) ] • Elevated Blood Pressure [see Warnings and Precautions (5.3) ] • Increased Risk of Bleeding [see Warnings and Precautions (5.4) ] • Angle-Closure Glaucoma [see Warnings and Precautions (5.5) ] • Activation of Mania/Hypomania [see Warnings and Precautions (5.6) ] • Discontinuation Syndrome [see Warnings and Precautions (5.7) ] • Seizure [see Warnings and Precautions (5.8) ] • Hyponatremia [see Warnings and Precautions (5.9) ] • Weight and Height Changes in Pediatric Patients [see Warnings and Precautions (5.10) ] • Appetite Changes in Pediatric Patients [see Warnings and Precautions (5.11) ] • Interstitial Lung Disease and Eosinophilic Pneumonia [see Warnings and Precautions (5.12) ] • Sexual Dysfunction [see Warnings and Precautions (5.13) ] Most common adverse reactions (incidence ≥5% and at least twice the rate of placebo): nausea, somnolence, dry mouth, sweating, abnormal ejaculation, anorexia, constipation, impotence (men), and libido decreased ( 6.1 ).
Source: FDA drug label, NDA020699 (Upjohn), as published by Viatris Specialty LLC, effective August 15, 2023 (SPL set c848a5d8-ba94-4c84-80e3-0bf35fb8e32e), via openFDA; the full label on DailyMed
What do FAERS reports show?
131,560 reports list venlafaxine among the medicines taken, each a report of something that happened, not proof the medicine caused it; 13,161 are coded as a death and 41,895 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 18 reactions below, 10 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Venlafaxine: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions