What Is Serotonin Syndrome? What You Need to Know If You Take SSRIs
Serotonin syndrome is a reaction to commonly prescribed medications and supplements. Learn what serotonin syndrome is, what causes it, and how to treat it.
phenelzine
Used for Depression
Used for Depression
Phenelzine sulfate, also known by its brand name Nardil, is used to treat adults with depression. This medication is a tablet that's taken by mouth. Phenelzine (Nardil) belongs to the drug class called monoamine oxidase inhibitors (MAOIs), which are generally not a first-choice option for depression. This is because the medication has many food and drug interactions. Phenelzine (Nardil) can also cause several bothersome side effects, such as sleepiness, weight gain, and sexual health problems.
What is Phenelzine (Nardil)?
What is Phenelzine (Nardil) used for?
How Phenelzine (Nardil) works
Phenelzine (Nardil) is a monoamine oxidase inhibitor (MAOI). It works by blocking MAO type A (MAO-A) and MAO type B (MAO-B), which are proteins in the body that break down certain chemicals like dopamine, serotonin, and norepinephrine in the brain. These chemicals play a role in regulating mood.
By blocking MAO-A and MAO-B, phenelzine (Nardil) keeps the levels of these chemicals high in the brain. This is thought to help treat symptoms of depression.
Drug facts
| Common Brands | Nardil |
|---|---|
| Drug Class | MAOI |
| Controlled Substance Classification | Not a controlled medication |
| Generic Status | Lower-cost generic available |
| Availability | Prescription only |
Side effects of Phenelzine (Nardil)
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Common Side Effects
- Dizziness
- Headache
- Drowsiness
- Sleep problems (too tired or trouble sleeping)
- Tiredness
- Weakness
- Shakiness (tremors)
- Twitching
- Overactive reflexes
- Constipation
- Stomach upset
- Dry mouth
- Weight gain
- Low blood pressure when you stand up
- Swelling
- Sexual health problems (e.g., erectile dysfunction, problems with orgasms)
Less Common Side Effects
- Blurry vision
- Eye movements that you can't control
- Itchiness
- Sweating
- Feeling jittery
- Numbness or tingling
- Repeating your words
- Bladder problems
Phenelzine (Nardil) serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Suicidal thoughts or behaviors
- Extremely high blood pressure: seizure, chest pain, severe headache, frequent headaches, confusion, blurry vision, anxiety, trouble breathing
- Serotonin syndrome: hallucinations, seizure, confusion, restlessness, shivering, sweating, high fever, headache, racing heart, muscle stiffness or twitching, tremor
The following Phenelzine (Nardil) side effects have also been reported
Along with its needed effects, a medicine 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:
More common
Chills
cold sweats
confusion
dizziness, faintness, or lightheadedness when getting up from a lying or sitting position
overactive reflexes
shakiness in the legs, arms, hands, or feet
sudden jerky movements of the body
swelling
trembling or shaking of the hands or feet
Less common
Abdominal or stomach pain
actions that are out of control
burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
change in consciousness
clay-colored stools
dark urine
decrease in frequency of urination
decrease in urine volume
difficult or troubled breathing
difficulty in passing urine (dribbling)
disorganized thoughts
dizziness
drowsiness
false or unusual sense of well-being
fast, pounding, or irregular heartbeat or pulse
fear or nervousness
general feeling of discomfort, illness, or weakness
headache
increased sweating
irregular, fast or slow, or shallow breathing
irritability
lack of emotion or feelings
loss of appetite
loss of consciousness
loud or fast speech
muscle tremors
muscle twitching
nausea or vomiting
nervousness
no emotion or expression in speech
pale or blue lips, fingernails, or skin
rapid, deep, or shallow breathing
rash
restlessness
seeing or hearing things that are not there
seizures
shakiness and unsteady walk
shortness of breath
slow or irregular heartbeat
stomach cramps
sweating
swelling of the feet or lower legs
talking, feeling, and acting with excitement
uncontrolled eye movements
unpleasant breath odor
unsteadiness, trembling, or other problems with muscle control or coordination
unusual paleness
unusual tiredness or weakness
vomiting of blood
weakness
yellow eyes or skin
Some side effects 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:
More common
decreased interest in sexual intercourse
inability to have or keep an erection
indigestion
loss in sexual ability, desire, drive, or performance
loss of appetite
not able to have an orgasm
passing of gas
stomach pain, fullness, or discomfort
trouble sleeping
unable to sleep
unusually deep sleep
unusually long duration of sleep
Less common
Blindness
blurred vision
decreased vision
redness, swelling, or soreness of the tongue
tearing
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Get your GoodRx coupon
$89.54
GoodRx discount
$30.40
Pros and cons of Phenelzine (Nardil)
Pros
- Can take with or without food
- Available as tablets taken by mouth
- Possible option for treating depression when other antidepressants haven't worked well
Cons
- Not a first-choice treatment option because of the risk of serious side effects
- Has many drug interactions
- Must follow specific food restrictions to lessen risk for having very high blood pressure
Pharmacist tips for Phenelzine (Nardil)
- You can take phenelzine (Nardil) with or without food. If phenelzine (Nardil) is hurting your stomach, taking it with food might help.
- Let your care team know that you're taking phenelzine (Nardil). There are a lot of medications that phenelzine (Nardil) can interact with and raise your risk for serious side effects. You have to wait at least 2 weeks after stopping phenelzine (Nardil) to safely start a new antidepressant or some other medications. This allows enough time for phenelzine (Nardil) to get out of your system completely.
- Ask your care team about what foods to avoid while you're taking phenelzine (Nardil). You'll have to limit certain foods and beverages because they can raise your risk for dangerously high blood pressure during treatment. Get medical help right away if you have symptoms of very high blood pressure like chest pain, severe headache, confusion, and blurred vision.
- Phenelzine (Nardil) can cause sleepiness and dizziness. Don't drive or do other things that require concentration until you know how this medication affects you.
- Avoid alcohol while you're taking phenelzine (Nardil). Alcohol can make side effects like sleepiness and dizziness more intense and lead to accidents.
- Phenelzine (Nardil) can make you gain some weight. To lower your risk, talk with your healthcare team about ways to maintain a healthy body weight while you're taking this medication. They can help with planning balanced and nutritious meals with ingredients such as lean proteins, whole-grains, fruits, and vegetables. They can also help build a regular exercise routine that's appropriate for you.
- Let your prescriber know if any side effects from phenelzine (Nardil) bother you too much. They might adjust the dose of your medication.
- Never change your dose or stop taking phenelzine (Nardil) without talking to your prescriber first. Otherwise, it might lead to withdrawal symptoms like anxiety, irritation, flu-like symptoms, muscle spasms, and psychosis (losing touch with reality). Follow your prescriber's instructions to lower your dose slowly over time to stop the medication safely.
More on Phenelzine (Nardil) tips
Risks and warnings for Phenelzine (Nardil)
Phenelzine (Nardil) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Suicidal thoughts or behavior
- Risk factors: People 24 years or younger | History of depression or other mood problems | Starting phenelzine (Nardil) for the first time | Changes in phenelzine (Nardil) dose
Taking phenelzine (Nardil) can make your depression worse. It might also cause you to have thoughts of suicide or thoughts of harming yourself. The risk is highest if you're 24 years of age or younger, during the first few weeks of taking the medication, and when your dose changes.
Let your prescriber know if you or anyone around you notices that your depression gets worse or that you have unusual behavior like anxiety, panic attacks, feeling angry or irritated, and restlessness while you're taking phenelzine (Nardil). Call 911 right away if you have any suicidal thoughts.
Not for use alone in bipolar disorder
Depression can be the first sign of bipolar disorder. Taking antidepressants, like phenelzine (Nardil), by themselves can lead to a bipolar manic episode in people at risk for bipolar disorder.
Before you start taking phenelzine (Nardil), your prescriber will check to see whether you have or are at risk for bipolar disorder. Phenelzine (Nardil) isn't used to treat bipolar depression. Talk to your healthcare team right away if you or your loved ones notice unusual changes in your behavior. Signs of a bipolar manic episode include racing thoughts, restlessness, getting easily distracted, or unusual talkativeness.
Dangerously high blood pressure
- Risk factors: History of high blood pressure | Eating fermented or smoked foods | Drinking beer and wine | Taking certain medications that can raise blood pressure
Although rare, people can have dangerously high blood pressure while they're taking phenelzine (Nardil). The risk is higher if you eat tyramine-rich foods, like aged cheese, cured or smoked meats, and pickled or fermented food, while you're taking this medication. Talk with your healthcare team about what other types of foods and drinks to avoid.
In addition, taking certain medications with phenelzine (Nardil) can raise your risk for extremely high blood pressure. Be sure to let your healthcare team know about all the medication you take or plan to take. They can check your risk for dangerously high blood pressure and make changes to your treatment plan to keep you safe.
Let your prescriber know if you check your blood pressure regularly and it's consistently higher than usual. Extremely high blood pressure is a medical emergency. Stop taking phenelzine (Nardil) and call 911 right away if you have any symptoms of dangerously high blood pressure. Look out for severe or frequent headache, chest pain, a racing heart, confusion, and blurry vision.
Serotonin syndrome
- Risk factors: Taking other medications that can affect serotonin
Some people who take phenelzine (Nardil) with other medications that raise serotonin levels can have a rare, but potentially life-threatening condition called serotonin syndrome. These medications can include other antidepressants and certain other mental health medications. Let your prescribers know about all your medications so they can make sure it's safe for you to take your medications together.
Get medical help right away if you have any symptoms of serotonin syndrome. These symptoms can include fast heart rate, sweating, muscle stiffness or spasms, fever, and confusion.
Phenelzine (Nardil) dosage
The average cost for 120 tablets of 15mg of Phenelzine (Nardil) is $30.40 with a free GoodRx coupon. This is 66.05% off the average retail price of $89.54. 
Tablet
Tablet| Dosage | Quantity | Price as low as | Price per unit |
|---|---|---|---|
| 15mg | 120 tablets | $30.40 | $0.25 |
Typical dosage for Phenelzine (Nardil)
The typical starting dose is 15 mg by mouth three times a day. Then, your prescriber will typically raise the dose to a total of 60 mg to 90 mg per day.
After you've gotten the maximum benefit from the medication, your prescriber will lower your dosage over several weeks to a maintenance dose. Maintenance doses can sometimes be as low as 15 mg every day or every other day.
In general, your prescriber will adjust your dose based on how well phenelzine (Nardil) works to help with your depression symptoms and whether you're having bothersome or serious side effects.
Interactions between Phenelzine (Nardil) and other drugs
Phenelzine (Nardil) may interact with certain medications or supplements. Always let your doctor and pharmacist know about any other medications or supplements (including prescribed and over-the-counter medications, vitamins, and dietary or herbal supplements) that you are currently taking. The list below does not include all possible drug interactions with Phenelzine (Nardil). Please note that only the generic name of each medication is listed below.
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
- Amitriptyline
- Amoxapine
- Amphetamine
- Apraclonidine
- Atomoxetine
- Benzphetamine
- Brimonidine
- Bupropion
- Buspirone
- Carbamazepine
- Carbidopa
- Carbinoxamine
- Citalopram
- Clomipramine
- Clovoxamine
- Cocaine
- Codeine
- Cyclobenzaprine
- Cyproheptadine
- Desipramine
- Desvenlafaxine
- Deutetrabenazine
- Dexfenfluramine
- Dexmethylphenidate
- Dextroamphetamine
- Dextromethorphan
- Diethylpropion
- Dopamine
- Doxylamine
- Duloxetine
- Entacapone
- Epinephrine
- Escitalopram
- Femoxetine
- Fenfluramine
- Fluoxetine
- Fluvoxamine
- Guanadrel
- Guanethidine
- Hydroxytryptophan
- Imipramine
- Isocarboxazid
- Isometheptene
- Levodopa
- Levomethadyl
- Levomilnacipran
- Linezolid
- Lisdexamfetamine
- Maprotiline
- Mazindol
- Meperidine
- Mephentermine
- Methamphetamine
- Methotrimeprazine
- Methyldopa
- Methylene Blue
- Methylphenidate
- Milnacipran
- Mirtazapine
- Nefazodone
- Nefopam
- Norepinephrine
- Nortriptyline
- Opicapone
- Opipramol
- Ozanimod
- Paroxetine
- Phendimetrazine
- Phenmetrazine
- Phentermine
- Phenylalanine
- Phenylephrine
- Phenylpropanolamine
- Procarbazine
- Protriptyline
- Pseudoephedrine
- Rasagiline
- Reserpine
- Rizatriptan
- Safinamide
- Selegiline
- Serdexmethylphenidate
- Sertraline
- Sibutramine
- Solriamfetol
- Sumatriptan
- Tapentadol
- Tetrabenazine
- Tramadol
- Tranylcypromine
- Trazodone
- Trimipramine
- Tryptophan
- Venlafaxine
- Vilazodone
- Viloxazine
- Vortioxetine
- Zolmitriptan
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Alfentanil
- Atropine
- Benzhydrocodone
- Buprenorphine
- Butorphanol
- Difenoxin
- Dihydrocodeine
- Diphenoxylate
- Dolasetron
- Dothiepin
- Doxepin
- Droperidol
- Ephedrine
- Ethchlorvynol
- Fentanyl
- Frovatriptan
- Granisetron
- Guarana
- Hydrocodone
- Hydromorphone
- Iobenguane I 123
- Iobenguane I 131
- Kava
- Lasmiditan
- Levorphanol
- Licorice
- Lithium
- Lofepramine
- Lorcaserin
- Ma Huang
- Mate
- Metaraminol
- Metaxalone
- Methadone
- Metoclopramide
- Midodrine
- Morphine
- Morphine Sulfate Liposome
- Nalbuphine
- Naratriptan
- Ondansetron
- Oxycodone
- Oxymetazoline
- Oxymorphone
- Palonosetron
- Pentazocine
- Reboxetine
- Remifentanil
- St John's Wort
- Sufentanil
- Tolcapone
- Tyrosine
- Valbenazine
- Ziprasidone
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Acarbose
- Chlorpropamide
- Ginseng
- Glimepiride
- Glipizide
- Glyburide
- Insulin
- Insulin Aspart, Recombinant
- Insulin Bovine
- Insulin Degludec
- Insulin Detemir
- Insulin Glargine, Recombinant
- Insulin Glulisine
- Insulin Lispro, Recombinant
- Metformin
- Metoprolol
- Nadolol
- Nateglinide
- Repaglinide
- Tolazamide
- Tolbutamide
How much does Phenelzine (Nardil) cost?
To access savings, use a GoodRx coupon and pay just a fraction of the retail price.
Phenelzine (Nardil) contraindications
Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Phenelzine (Nardil) will not be safe for you to take.
- Heart failure
- Severe kidney problems
- Liver problems
- Pheochromocytoma (a type of adrenal gland tumor)
- Surgery that requires general anesthesia
- Eat foods with high amounts of tyramine or dopamine
- Take with alcohol
- Take with meperidine or certain other opioids
- Take with stimulant medications like phentermine (Adipex-P) or Adderall (amphetamine salt combination)
- Take with medications containing dextromethorphan
- Take with medications that raise serotonin levels
- Take with buspirone (Buspar), buproprion, or other antidepressants
What are alternatives to Phenelzine (Nardil)?
There are a number of medications that your doctor can prescribe in place of Phenelzine (Nardil). Compare a few possible alternatives below.
News about Phenelzine (Nardil)
5 Outdated Migraine Medications You May Want to Upgrade
Some migraine medications have largely been replaced by safer or more effective options. Learn about the newer treatments available today with this guide.
How to Help Someone With Depression
Has a loved one’s struggle with depression left you unsure of how to support them? Learn about depression and the ways you can help.
7 Foods to Consider Avoiding If You’re Taking an MAOI
While taking MAOIs, it’s important to follow a low-tyramine diet and restrict foods, such as aged meats and cheeses, to avoid dangerously high blood pressure.
What Is Antidepressant Discontinuation Syndrome? Withdrawal from Antidepressants Explained
Antidepressant discontinuation syndrome (antidepressant withdrawal) occurs when you quickly stop or lower the dose of your antidepressant. Here’s why it happens and how you can avoid it.
Getting Anxiety Medication: 9 Things to Know When Starting Treatment
Treating anxiety is the first step to living well. Find out how you can get anxiety medication from your provider and what you need to know about treatment.
Postpartum Depression in Men: Signs and Symptoms of This Under-Recognized Condition
People are becoming more familiar with the signs of postpartum depression in women. But men can develop it as well. Find out more about postpartum depression in men, here.
Phenelzine (Nardil) images
