Levomilnacipran Side Effects

Medically reviewed by Drugs.com. Last updated on Mar 8, 2025.

Applies to levomilnacipran: oral capsule extended release.

Precautions

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly.

Do not take levomilnacipran with a monoamine oxidase (MAO) inhibitor (eg, isocarboxazid [Marplan®], phenelzine [Nardil®], selegiline [Eldepryl®], tranylcypromine [Parnate®]). Do not start taking levomilnacipran during the 2 weeks after you stop a MAO inhibitor. Wait 1 week after stopping levomilnacipran before you start taking a MAO inhibitor. Do not use this medicine if you are using certain MAOI (eg, linezolid [Zyvox®], methylene blue injection). If you take them together or do not wait the proper amount of time, you may develop confusion, agitation, restlessness, stomach or intestinal symptoms, a sudden high body temperature, an extremely high blood pressure, or severe seizures.

Levomilnacipran may cause some teenagers and young adults to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. Some people may have trouble sleeping, get upset easily, have a big increase in energy, or start to act reckless. If you or your caregiver notice any of these unwanted effects, tell your doctor right away. Let the doctor know if you or anyone in your family has bipolar disorder (manic-depressive) or has tried to commit suicide.

Levomilnacipran may cause a serious condition called serotonin syndrome if taken together with some medicines. Do not use levomilnacipran with buspirone (Buspar®), fentanyl (Abstral®, Duragesic®), lithium (Eskalith®, Lithobid®), tryptophan, St. John's wort, amphetamines, or some pain or migraine medicines (eg, meperidine, methadone, rizatriptan, sumatriptan, tramadol, Demerol®, Methadose®, Frova®, Imitrex®, Maxalt®, Relpax®, Ultram®, Zomig®). Check with your doctor first before taking any other medicines with levomilnacipran.

This medicine may increase your risk for bleeding problems. Make sure your doctor knows if you are also taking other medicines that thin the blood, including aspirin, nonsteroidal antiinflammatory agents, also called NSAIDs (eg, diclofenac, ibuprofen, naproxen, Advil®, Aleve®, Celebrex®, Voltaren®), or warfarin (Coumadin®, Jantoven®).

Do not Stop taking levomilnacipran without checking first with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping it completely to decrease the chance of withdrawal effects. Some examples of withdrawal effects include agitation, breathing problems, chest pain, confusion, diarrhea, dizziness or lightheadedness, fast heartbeat, headaches, increased sweating, muscle pain, nausea, restlessness, runny nose, trouble sleeping, trembling or shaking, unusual tiredness or weakness, vision changes, or vomiting.

This medicine may cause hyponatremia (low sodium in the blood). This is more common in elderly patients, those who are taking diuretic medicines, or those who have less fluid in the body due to severe diarrhea or vomiting. Check with your doctor right away if you have confusion, a headache, memory problems, trouble concentrating, weakness, or feel unsteady when standing.

This medicine may cause some people to become dizzy, drowsy, or less alert than they are normally. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are not alert.

Check with your doctor right away if you have decreased interest in sexual intercourse, delayed or inability to have an orgasm in women, inability to have or keep an erection in men, or loss in sexual ability, desire, drive, or performance. These could be symptoms of sexual dysfunction.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal (eg, St. John's wort) or vitamin supplements.

Serious side effects of levomilnacipran

Along with its needed effects, levomilnacipran may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking levomilnacipran:

Other side effects of levomilnacipran

Some side effects of levomilnacipran may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to levomilnacipran: oral capsule extended release.

General adverse events

The most commonly reported side effects included nausea, erectile dysfunction, constipation, and hyperhidrosis.^[Ref]

Gastrointestinal

• Very common (10% or more): Nausea (up to 17%)
• Common (1% to 10%): Constipation, vomiting
• Frequency not reported: Abdominal pain, flatulence^[Ref]

Cardiovascular

• Common (1% to 10%): Hot flush, hypertension, hypotension, increased blood pressure, increased heart rate, palpitations, tachycardia
• Frequency not reported: Angina pectoris, chest pain, increased diastolic blood pressure, increased orthostatic blood pressure, increased orthostatic heart rate response, increased systolic blood pressure, labile hypertension, orthostatic hypotension, postural orthostatic tachycardia syndrome, sinus tachycardia, supraventricular extrasystoles, ventricular extrasystoles
• Postmarketing reports: Takotsubo cardiomyopathy^[Ref]

Genitourinary

• Common (1% to 10%): Ejaculation disorder, erectile dysfunction, testicular pain, urinary hesitation
• Frequency not reported: Ejaculation delayed, ejaculation failure, epididymitis, hematuria, organic erectile dysfunction, pollakiuria, proteinuria, seminal vesiculitis, urinary hesitation, urinary retention^[Ref]

Erectile dysfunction and urinary hesitation occurred as dose-related events.^[Ref]

Dermatologic

• Common (1% to 10%): Hyperhidrosis, rash
• Frequency not reported: Dry skin, erythematous rash, generalized rash, macular rash, maculopapular rash, pruritus, urticaria^[Ref]

Metabolic

• Common (1% to 10%): Decreased appetite
• Frequency not reported: Hyponatremia, increased blood cholesterol, thirst^[Ref]

Psychiatric

• Frequency not reported: Aggression, agitation, anger, bruxism, hypomania activation, mania activation, panic attack, premature ejaculation, psychogenic erectile dysfunction, suicidal behaviors, suicidal thoughts, tension^[Ref]

Suicidal thoughts and behaviors more commonly occurred in adolescent and young adults 24 years and younger.^[Ref]

Nervous system

• Frequency not reported: Extrapyramidal disorder, migraine, paresthesia, postural dizziness, seizure, serotonin syndrome, syncope^[Ref]

Ocular

• Frequency not reported: Angle closure glaucoma, blurred vision, conjunctival hemorrhage, dry eye^[Ref]

Other

• Frequency not reported: Discontinuation syndrome^[Ref]

Hypersensitivity

• Frequency not reported: Hypersensitivity^[Ref]

Hematologic

• Frequency not reported: Increased bleeding risk^[Ref]

Hepatic

• Frequency not reported: Abnormal liver function tests^[Ref]

Respiratory

• Frequency not reported: Yawning^[Ref]

See also:

Frequently asked questions

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Further information

Levomilnacipran side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer