It is important that your doctor check your progress at regular visits, to allow for changes in your dose and to help reduce any side effects .
Venlafaxine may cause some people 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. If you, your child, or your caregiver notice any of these side effects, tell your doctor or your child's doctor right away .
Do not stop taking this medicine without first checking with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping completely. This is to decrease the chance of side effects .
Do not take venlafaxine within 2 weeks (14 days) of taking a monoamine oxidase (MAO) inhibitor (e.g., isocarboxazid [Marplan®], phenelzine [Nardil®], selegiline [Eldepryl®], or tranylcypromine [Parnate®]), and do not take an MAO inhibitor for at least 7 days after taking venlafaxine. If you do, you may develop serious side effects such as seizures .
Make sure your doctor knows about all the other medicines you are using. Venlafaxine may cause a serious condition called serotonin syndrome when taken with certain medicines such as linezolid [e.g., Zyvox®], lithium, tryptophan, St. John's Wort, or some pain or migraine medicines (e.g., tramadol [Ultram®], sumatriptan [Imitrex®], zolmitriptan [Zomig®], or rizatriptan [Maxalt®]). Check with your doctor first before taking any other medicines .
It is not known how venlafaxine will interact with alcohol and other central nervous system (CNS) depressants (medicines that may make you drowsy or less alert). Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; barbiturates; medicine for seizures; muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any of these medicines while you are using venlafaxine .
Venlafaxine may cause some people to become drowsy or have blurred vision. 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 or able to see clearly .
Dizziness, light-headedness, or fainting may occur with this medicine, especially when you get up quickly from a lying or sitting position. Getting up slowly may help. If this problem continues or gets worse, check with your doctor .