Warnings for Effexor
The most important thing to know before taking Effexor is that it must not be used in combination with MAO inhibitors (for example, Nardil [Phenelzine], Marplan [isocarboxazid] and Parnate [tranylcypromine]). Serious and even fatal complications may result from such a combination. In addition, wait 14 days after discontinuing the MAOI before starting Effexor, and 7 days after discontinuing Effexor before starting an MAOI.
Dr. Ivan Goldberg recommends starting at low dose and building up gradually, and also warns against stopping use of Effexor abruptly. Withdrawal syndrome, which may be severe and prolonged, can occur even if the medication is tapered off. Symptoms may include: headaches, nausea, dizziness, unstable moods, gastrointestinal upset, recurrence of depression, bizarre dreams, paraesthesiae (abnormal sensations of burning, prickling, tingling, etc.), or auditory hallucinations.
While the registered side effects list for Effexor/Venlafaxine is not long, some sources say many more side effects exist that are not registered. Therefore, it is very important to monitor your physical and mental condition closely while you are taking this drug.
Other Precautions
Make sure your doctor knows your complete medical history. Effexor may not be a good choice if you have a history of:
- Brain disease or damage, or mental retardation or
- Seizures (history of) - The risk of seizures may be increased
- Heart disease or
- High or low blood pressure - Venlafaxine may make these conditions worse
- Kidney disease or
- Liver disease - Higher blood levels of venlafaxine may occur, increasing the chance of side effects; your doctor may need to adjust your venlafaxine dose
- Mania (history of) - The risk of developing mania may be increased; obviously this is very important for bipolar patients to watch for
- Weight loss - Venlafaxine may cause weight loss; this weight loss is usually small, but if a large weight loss occurs, it may be harmful in some patients
- It may take several weeks for the effects of this medication to kick in.
- Take as directed, with food, and do not break, crush or chew tablets or open the capsules.
- If you miss a dose, do not take a double dose to make up.
- Be cautious for side effects when taking any over-the-counter medications with Effexor.
- Health Square indicates that elderly persons or those with liver disease or high blood pressure should check with their physicians before combining Effexor with Tagamet (cimetidine).
- Health Square (above) also reports that this medication may cause water retention in the elderly.
- Nausea is the most commonly reported side effect. The manufacturer says this will usually diminish within two weeks.
- According to the Mayo Clinic [link no longer available], animal test results show that use of Effexor while pregnant or nursing may not be wise, and there have been no controlled studies to date in pregnant women.
Conclusions
Effexor may be a good choice for treatment-resistant depression or depression with anxiety. When taking this medication, however, report anything unusual to your doctor, as side effects have been reported that are not listed in the patient insert. These additional side effects are said to be rare, but it's best to be cautious.
Disclaimer: This profile is not intended to be all-inclusive or to replace information provided by your doctor or with the prescription from the manufacturer.

