This medication is used to treat certain mental/mood
disorders (such as depression, anxiety, panic attacks, and social anxiety
disorder). Venlafaxine belongs to a class of drugs known as
serotonin-norepinephrine reuptake inhibitors (SNRIs). It works by helping
to restore the balance of certain natural substances (serotonin and
norepinephrine) in the brain.
This section contains uses of this drug that are not
listed in the approved professional labeling for the drug but that may be
prescribed by your health care professional. Use this drug for a condition
that is listed in this section only if it has been so prescribed by your
health care professional.
This drug may also be used for hot flashes that occur
with menopause. It may also be used for nerve pain.
Read the Medication Guide and, if available, the Patient
Information Leaflet provided by your pharmacist before you start using
venlafaxine and each time you get a refill. If you have any questions, ask
your doctor or pharmacist.
Take this medication by mouth as directed by your
doctor, usually once daily with food, either in the morning or
evening.
Do not crush, chew, or dissolve this medication. Doing
so can release all of the drug at once, increasing the risk of side
effects. Swallow whole without crushing or chewing.
If you are taking the capsules, swallow them whole. If
you have trouble swallowing the capsules whole, you may open the capsule
and sprinkle the contents onto a spoonful of applesauce. Swallow all of the
mixture right away without chewing. Drink a glass of water after each
dose.
The dosage is based on your medical condition and
response to treatment. To reduce your risk of side effects, your doctor may
direct you to start this medication at a low dose and gradually increase
your dose. Follow your doctor's instructions carefully. Take this
medication regularly to get the most benefit from it. To help you remember,
take it at the same time each day.
Keep taking this medication even if you feel well. Do
not stop taking this medication without consulting your doctor. Some
conditions may become worse when this drug is suddenly stopped. Also, you
may experience symptoms such as confusion, mood swings, blurred vision,
headache, tiredness, sleep changes, and brief feelings similar to electric
shock. Your dose may need to be gradually decreased to reduce side effects.
Report any new or worsening symptoms right away.
It may take several weeks to feel the benefit of this
medication. Tell your doctor if your condition lasts or gets
worse.
See also Warning section.
Nausea, drowsiness, dizziness, dry mouth, constipation,
loss of appetite, blurred vision, nervousness, trouble sleeping, unusual
sweating, or yawning may occur. If any of these effects last or get worse,
tell your doctor promptly.
Remember that this medication has been prescribed
because your doctor has judged that the benefit to you is greater than the
risk of side effects. Many people using this medication do not have serious
side effects.
This medication may raise your blood pressure. Check
your blood pressure regularly and tell your doctor if the results are
high.
Tell your doctor right away if you have any serious side
effects, including:
- easy bleeding/bruising
- decreased interest in sex
- changes in sexual ability
- muscle cramps/weakness
- shaking (tremor)
Get medical help right away if you have any very serious
side effects, including:
- cough that doesn't go away
- shortness of breath
- chest pain
- severe/pounding headache
- black stools
- vomit that looks like coffee grounds
- eye pain/swelling/redness
- widened pupils
- vision changes (such as seeing rainbows around lights at
night)
- seizure
This medication may increase serotonin and rarely cause
a very serious condition called serotonin syndrome/toxicity. The risk
increases if you are also taking other drugs that increase serotonin, so
tell your doctor or pharmacist of all the drugs you take (see Drug
Interactions section). Get medical help right away if you develop some of
the following symptoms:
- fast heartbeat
- hallucinations
- loss of coordination
- severe dizziness
- severe nausea/vomiting/diarrhea
- twitching muscles
- unexplained fever
- unusual agitation/restlessness
A very serious allergic reaction to this drug is rare.
However, get medical help right away if you notice any symptoms of a
serious allergic reaction, including:
- rash
- itching/swelling (especially of the face/tongue/throat)
- severe dizziness
- trouble breathing
This is not a complete list of possible side effects. If
you notice other effects not listed above, contact your doctor or
pharmacist.
In the US - Call your doctor for medical advice about side effects.
You may report side effects to FDA at 1-800-FDA-1088 or at
www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about
side effects. You may report side effects to Health Canada at
1-866-234-2345.
Before taking venlafaxine, tell your doctor or
pharmacist if you are allergic to it; or to desvenlafaxine; or if you have
any other allergies. This product may contain inactive ingredients, which
can cause allergic reactions or other problems. Talk to your pharmacist for
more details.
Before using this medication, tell your doctor or
pharmacist your medical history, especially of:
- bleeding problems
- personal or family history of glaucoma (angle-closure
type)
- high blood pressure
- heart problems (such as heart failure, previous heart
attack)
- high cholesterol
- kidney disease
- liver disease
- seizure disorder
- thyroid disease
This drug may make you dizzy or drowsy or blur your
vision. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy.
Do not drive, use machinery, or do anything that needs alertness or clear
vision until you can do it safely. Avoid alcoholic beverages. Talk to your
doctor if you are using marijuana (cannabis).
Before having surgery, tell your doctor or dentist about
all the products you use (including prescription drugs, nonprescription
drugs, and herbal products).
Older adults may be more sensitive to the side effects
of this drug, especially dizziness when standing. Older adults may also be
more likely to develop a type of salt imbalance (hyponatremia), especially
if they are taking "water pills" (diuretics). Dizziness and salt imbalance
can increase the risk of falling. Older adults may also be at greater risk
for bleeding while using this drug.
Children may be more sensitive to the side effects of
the drug, especially loss of appetite and weight loss. Monitor weight and
height in children who are taking this drug.
During pregnancy, this medication should be used only
when clearly needed. It may harm an unborn baby. Also, babies born to
mothers who have used this drug during the last 3 months of pregnancy may
rarely develop withdrawal symptoms such as feeding/breathing difficulties,
seizures, muscle stiffness, or constant crying. If you notice any of these
symptoms in your newborn, tell the doctor promptly.
Since untreated mental/mood problems (such as
depression, anxiety, panic attacks) can be a serious condition, do not stop
taking this medication unless directed by your doctor. If you are planning
pregnancy, become pregnant, or think you may be pregnant, immediately
discuss the benefits and risks of using this medication during pregnancy
with your doctor.
This drug passes into breast milk and may have
undesirable effects on a nursing infant. Consult your doctor before
breastfeeding.
Drug interactions may change how your medications work
or increase your risk for serious side effects. This document does not
contain all possible drug interactions. Keep a list of all the products you
use (including prescription/nonprescription drugs and herbal products) and
share it with your doctor and pharmacist. Do not start, stop, or change the
dosage of any medicines without your doctor's approval.
Some products that may interact with this drug
are:
- other drugs that can cause bleeding/bruising (including
antiplatelet drugs such as clopidogrel, NSAIDs such as ibuprofen/naproxen,
"blood thinners" such as dabigatran/warfarin)
Aspirin can increase the risk of bleeding when used with
this medication. However, if your doctor has told you to take low-dose
aspirin to prevent heart attack or stroke (usually 81-162 milligrams a
day), you should keep taking the aspirin unless your doctor tells you not
to. Ask your doctor or pharmacist for more details.
Taking MAO inhibitors with this medication may cause a
serious (possibly fatal) drug interaction. Avoid taking MAO inhibitors
(isocarboxazid, linezolid, metaxalone, methylene blue, moclobemide,
phenelzine, procarbazine, rasagiline, safinamide, selegiline,
tranylcypromine) during treatment with this medication. Most MAO inhibitors
should also not be taken for two weeks before and at least 7 days after
treatment with this medication. Ask your doctor when to start or stop
taking this medication.
The risk of serotonin syndrome/toxicity increases if you
are also taking other drugs that increase serotonin. Examples include
street drugs such as MDMA/"ecstasy," St. John's wort, certain
antidepressants (including SSRIs such as fluoxetine/paroxetine, other SNRIs
such as duloxetine/milnacipran), tryptophan, among others. The risk of
serotonin syndrome/toxicity may be more likely when you start or increase
the dose of these drugs.
Tell your doctor or pharmacist if you are taking other
products that cause drowsiness such as opioid pain or cough relievers (such
as codeine, hydrocodone), alcohol, marijuana (cannabis), drugs for sleep or
anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such
as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine,
diphenhydramine).
Check the labels on all your medicines (such as allergy
or cough-and-cold products) because they may contain ingredients that cause
drowsiness. Ask your pharmacist about using those products
safely.
Venlafaxine is very similar to desvenlafaxine. Do not
take medications containing desvenlafaxine while using
venlafaxine.
This medication may interfere with certain lab tests
(including urine tests for amphetamines), possibly causing false test
results. Make sure lab personnel and all your doctors know you use this
drug.
If someone has overdosed and has serious symptoms such
as passing out or trouble breathing, call 911. Otherwise, call a poison
control center right away. US residents can call 1-800-222-1222. Canada
residents can call 1-844-764-7669. Symptoms of overdose may include: severe
drowsiness, seizures, fast/irregular heartbeat.
Do not share this medication with others.
Lab and/or medical tests (such as blood pressure,
cholesterol) should be done while you are taking this medication. Keep all
medical and lab appointments. Consult your doctor for more
details.
If you miss a dose, take it as soon as you remember. If
it is near the time of the next dose, skip the missed dose. Take your next
dose at the regular time. Do not double the dose to catch
up.
Store at room temperature away from light and moisture.
Do not store in the bathroom. Keep all medications away from children and
pets.
Do not flush medications down the toilet or pour them
into a drain unless instructed to do so. Properly discard this product when
it is expired or no longer needed. Consult your pharmacist or local waste
disposal company.