I started xanax xr.5 mg twice a day a couple days ago for anxiety and panic attacks due to stress and depression. I feel tired and foggy all the time. Effexor is a dual purpose antidepressant released by Wyeth-Ayerst Laboratories and approved by the FDA in October 1997. Effexor boosts serotonin levels in the synapse in similar fashion to other SSRI's. The new measures tend to extend the role of social security programs through providing a greater proportion of the population with more comprehensive protection and setting higher benefit rates to replace income lost because of old age, disability, sickness, work injury, unemployment, or death. Doctors give unbiased, trusted information on whether Alprazolam can cause or treat Slow Heart Rate: Dr. Husar on does xanax lower heart rate: Anxiety can increase your heart rate. If citalopram helps your anxiety, then your heart rate may decrease naturally. Xanax vs Zoloft. Depression is most often evident in a percentage of the population. Though it cannot be prevented, we humans can always consider a problem as a big deal or not. Zoloft and most SSRI / SNRI's take roughly one to two weeks to take effect. Some people experience a positive effect sooner, and some don't respond to the medication, and possibly the dosage needs to be increased, and or a different medication needs to be given a try. Get Help. If you need help please visit or call 1-800-442-HOPE. Demystifying Depression is a great article which helped me understand some of the ways depression was affecting me. More young people are using Xanax – but overdose, addiction and side effects present serious risks. I have stopped taking Xanax. My memory loss was pretty bad. Do you know how long it will be before I get my memory back? Hello there, The usual starting Xanax dosage is 0.25 mg to 0.5 mg taken three times a day or as needed. If you take more than 4 mg per day, you are at risk of extreme physical or mental dependence.