Venlafaxine
Does it work?
Yes. There's good research showing that venlafaxine works as well as other antidepressants for people with depression. Venlafaxine may work slightly better than selective serotonin reuptake inhibitors (SSRIs) in people with mild or moderate depression.
But venlafaxine can cause unpleasant side effects.
We don't know for certain how antidepressants compare with another good treatment called cognitive therapy. But if you have mild or moderate depression, cognitive therapy may work slightly better.
What is it?
Venlafaxine (brand name Efexor) is a fairly new antidepressant. It is a serotonin and noradrenaline reuptake inhibitor (or SNRI). This drug is similar to selective serotonin reuptake inhibitors (SSRIs). Venlafaxine is usually used after other antidepressants haven't worked.[8]
Your doctor will probably talk to you about what treatment you would like, if any. There are national guidelines for doctors on how to treat depression.[1] You might find them useful when discussing your treatment with your doctor. To learn more, see NICE guidance on depression.
You'll probably need to take antidepressants for more than six weeks before you start to feel better. So it's important not to stop taking them early.
How can it help?
Venlafaxine can help you with the symptoms of depression.
One study found that up to 8 in 10 people felt much better after treatment with venlafaxine.[9]
Taking an antidepressant can mean:
- You feel less sad, hopeless, worried or guilty
- Your appetite improves
- Your sex drive comes back
- You can concentrate better
- You no longer think about suicide.
Venlafaxine seems to work as well as other kinds of antidepressants.[5] [10] [11] It may work slightly better than selective serotonin reuptake inhibitors (SSRIs) for people with mild or moderate depression.[5] [4] [3]
Why should it work?
Antidepressants affect chemicals called neurotransmitters which help carry messages from brain cell to brain cell. In particular, venlafaxine boosts the amounts of the chemicals serotonin and noradrenaline. This gradually causes changes in how your brain cells behave. It can take several weeks before you can tell if the drugs are affecting your mood.
The problem is that the drugs also affect other brain cells, disrupting nerve signals and causing side effects.
Can it be harmful?
In the UK there is government advice for doctors on how to safely prescribe venlafaxine (and SSRI drugs). It says that people taking these drugs should be carefully checked in the early stages of treatment or when their dose is changed, especially if they have symptoms such as agitation and restlessness, or if their depression gets worse. People should also be on the lowest dose that works.[8]
Venlafaxine causes heart problems in some people. You need to have your blood pressure checked regularly when you're taking it.[12] You shouldn't take venlafaxine if you have certain heart problems or high blood pressure.
Studies show that up to 7 in 10 people treated with venlafaxine have side effects.[9] [10] This is similar for people taking an SSRI drug. But you'll probably get more side effects if you're treated with a tricyclic antidepressant.
Venlafaxine can cause sexual problems, such as problems with erections or difficulty having an orgasm.[13] You might also feel sick, tired or dizzy, or lose your appetite if you take this drug.
Here's what happened to people with depression who took venlafaxine in studies:[10] [9]
- 4 in 10 people had stomach problems
- More than a quarter had a dry mouth
- More than a third sweated more than normal
- Two-fifths lost weight.
All antidepressants can cause side effects. It's important to find the drug that suits you best.
Older people may be more likely to get side effects than younger people, whatever antidepressant they take. This is because of changes in the body that happen as people get older. Older people may also be on other medicines, so there's more chance of side effects from taking more than one drug.
Withdrawal symptoms
Venlafaxine can cause withdrawal symptoms if you stop taking it suddenly or if your dose is reduced. The most common symptoms are dizziness, sickness, headaches, a feeling that the room is spinning, and a feeling of numbness or tingling.[14] Other withdrawal symptoms are sweating, anxiety and problems sleeping.[8]
Talk to your doctor if you want to stop taking an antidepressant. And never stop your treatment suddenly. Your doctor can help you reduce your dose gradually over several weeks to reduce the risk that you'll get withdrawal symptoms.[8]
Self-harm and suicide
There is concern that venlafaxine (and most SSRIs) might make you more likely to harm yourself or think about suicide if you're an adult. But there's not enough research to say for sure whether there really is a risk.
Some reports suggest that these drugs might make children and teenagers more likely to harm themselves or think about suicide.[15] Doctors now think that most of these drugs do more harm than good when used to treat depression in children. An SSRI called fluoxetine (brand name Prozac) is the only drug which doctors are advised is suitable for children.
Doctors in different countries have been given different advice about prescribing these drugs. In the UK doctors are advised not to give venlafaxine to children or teenagers to treat depression.[8]
To learn more, see Antidepressants and suicide in children.
But researchers are still uncertain about whether SSRIs and venlafaxine are linked to self-harm and thoughts of suicide in adults. Different studies have had different results. Some very large studies have found that thoughts of suicide or suicide attempts are more likely if people take an SSRI. [16] [6] But other large studies have found that SSRIs are not linked with an increased risk of suicide. [17] [18] [19]
The authorities in the UK and the US have advised doctors to keep a careful eye on adults taking either an SSRI or venlafaxine to check for new symptoms or depression that gets worse.[8] [7] These changes are most likely to happen in the early stages of treatment or if there's a change of dose.[8]
If you are taking an antidepressant and are worried about any thoughts or feelings you have, see your doctor straight away.
Venlafaxine and migraine drugs
If you take migraine drugs called triptans with venlafaxine or another SNRI, you could get too much of the chemical serotonin in your body. This can lead to a condition called serotonin syndrome, which can cause serious side effects. To learn more, see Serotonin syndrome.
Can I take antidepressants if I'm pregnant?
There isn't much research on taking antidepressants if you're pregnant. Doctors are advised to avoid prescribing them to pregnant women, or to use them with care if the benefits are likely to outweigh the risks.[2] This is because of concerns that drugs taken during pregnancy might harm the baby. However, some research shows that pregnant women who stop taking their antidepressants are more likely to become depressed again.[20]
To learn more, see Antidepressants and pregnancy.
References
- National Institute for Clinical Excellence. Depression: management of depression in primary and secondary care. December 2004. Clinical guideline 23. Available at http://www.nice.org.uk/cg23 (accessed on 9 October 2007).
- British National Formulary. Pregnancy. Appendix 4. September 2007. BNF 54. British Medical Association and Royal Pharmaceutical Society of Great Britain. Also available at http://bnf.org (accessed on 9 October 2007).
- Cipriani A, Brambilla P, Furukawa T, et al. Fluoxetine versus other types of pharmacotherapy for depression (Cochrane review). In: The Cochrane Library, Issue 4, 2005. Wiley, Chichester, UK.
- Hansen RA, Gartlehner G, Lohr KN, et al Efficacy and safety of second-generation antidepressants in the treatment of major depressive disorder. Annals of Internal Medicine. 2005; 143: 415-426.
- Smith D, Dempster C, Glanville J, et al. Efficacy and tolerability of venlafaxine compared with selective serotonin reuptake inhibitors and other antidepressants: a meta-analysis. British Journal of Psychiatry. 2002; 180: 396-404.
- Jick SS, Dean AD, Jick H. Antidepressants and suicide. BMJ. 1995; 310: 215-218.
- U.S. Food and Drug Administration. Suicidality in adults being treated with antidepressant medications. June 2005. Available at http://www.fda.gov/cder/drug/antidepressants/historical.htm (accessed on 2 October 2007).
- Medicines and Healthcare products Regulatory Agency. Report of the CSM expert working group on the safety of selective serotonin reuptake inhibitor antidepressants. December 2004. Available at http://www.mhra.gov.uk (accessed on 9 October 2007).
- Montgomery SA, Huusom AK, Bothmer J. A randomised study comparing escitalopram with venlafaxine XR in primary care patients with major depressive disorder. Neuropsychobiology. 2004; 50: 57-64.
- Sauer H, Huppertz-Helmhold S, Dierkes W. Efficacy and safety of venlafaxine ER vs. amitriptyline ER in patients with major depression of moderate severity. Pharmacopsychiatry. 2003; 36: 169-175.
- Guelfi JD, Ansseau M, Timmerman L, et al. Mirtazapine versus venlafaxine in hospitalized severely depressed patients with melancholic features. Journal of Clinical Psychopharmacology. 2001; 21: 425-431.
- Commission on Human Medicines. Updated prescribing advice for venlafaxine (Efexor/Efexor XL): information for healthcare professionals.May 2006. Available at http://www.mhra.gov.uk (accessed on 9 October 2007). May 2006. Available at http://www.mhra.gov.uk (accessed on 9 October 2007).
- British National Formulary. Venlafaxine. Section 4.3.4. September 2007. BNF 54. British Medical Association and Royal Pharmaceutical Society of Great Britain. Also available at http://bnf.org (accessed on 9 October 2007).
- Stahl MM, Lindquist M, et al. Withdrawal reactions with selective serotonin re-uptake inhibitors as reported to the WHO system. European Journal of Clinical Pharmacology. 1997; 53: 163-169.
- Geddes JR, Cipriani A. Selective serotonin reuptake inhibitors. BMJ. 2004; 329: 809-810.
- Fergusson D, Doucette S, Glass KC, et al. Association between suicide attempts and selective serotonin reuptake inhibitors:systematic review of randomised controlled trials. BMJ. 2005; 330: 396-399.
- Martinez C, Rietbrock S, Wise L, et al. Antidepressant treatment and the risk of fatal and non-fatal self harm in first episode depression: nested case-control study. BMJ. 2005; 330: 389-393.
- Jick H, Kaye JA, Jick SS. Antidepressants and the risk of suicidal behaviours. Journal of the American Medical Association. 2004; 292: 338-343.
- Gunnell D, Saperia J, Ashby D. Selective serotonin reuptake inhibitors (SSRIs) and suicide in adults: meta-analysis of drug company data from placebo controlled, randomised controlled trials submitted to the MHRA's safety review. BMJ. 2005; 330: 385-388.
- U.S. Food and Drug Administration. Treatment challenges of depression in pregnancy and the possibility of persistent pulmonary hypertension in newborns. July 2006. Available at http://www.fda.gov/cder/drug/advisory/SSRI_PPHN200607.htm (accessed on 9 October 2007).
Glossary
- noradrenaline
- Noradrenaline is a neurotransmitter, which is a chemical that helps to send information between nerve cells. It is similar to adrenaline. Your body produces adrenaline when you're in stressful situations, which increases your blood pressure and heart rate.
- serotonin
- Serotonin is a neurotransmitter, which is a chemical that helps to send information from a nerve cell to other cells. It is thought to play a role in learning, sleep and control of mood.
- withdrawal symptoms
- Withdrawal symptoms are when you get unpleasant physical or mental symptoms because you stopped taking a drug you were physically dependent on. Your can become physically dependent on a drug if it alters the level of certain chemicals in your body. This makes your body produce less of those chemicals or change how it responds to them. Also, some drugs work in a similar way to chemicals that naturally occur in your body. This may mean your body stops making its natural versions. If either of those things happens, your body will need the drug to function normally and you will feel or become ill if you suddenly stop taking the drug. You can get withdrawal symptoms from some prescription medicines, as well as some illegal drugs.
- high blood pressure
- Your blood pressure is considered to be high when it is above the accepted normal range. The usual limit for normal blood pressure is 140/90. If either the first (systolic) number is above 140 or the lower (diastolic) number is above 90, a person is considered to have high blood pressure. Doctors sometimes call high blood pressure 'hypertension'.
- migraine headaches
- These are severe headaches that last four to 72 hours. They often cause other symptoms such as queasiness (nausea) or being extra-sensitive to sound or light.
© BMJ Publishing Group Limited ("BMJ Group") 2007. All rights reserved
This information does not replace medical advice. If you are concerned you might have a medical problem please ask your Boots pharmacy team in your local Boots store, or see your doctor.
