Patient information for MIRTAZAPINE 15 MG TABLETS Including dosage instructions and possible side effects. Applies to mirtazapine: oral tablet, oral tablet disintegrating. Along with its needed effects, mirtazapine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Describes the medication mirtazapine (Remeron, Soltab), a drug used for the treatment of depression and posttraumatic stress disorder (PTSD). Side effects and drug interactions are included in the information. Read more about the prescription drug mirtazapine (Remeron, Soltab). Pictures of Remeron (Mirtazapine), drug imprint information, side effects for the patient. SIDE EFFECTS Associated With Discontinuation Of Treatment. Approximately 16% of the 453 patients who received REMERON (mirtazapine) Tablets in US 6-week controlled clinical trials discontinued treatment due to an adverse experience, compared to 7% of the 361 placebo-treated patients in those studies. Posology. Adults. The effective daily dose is usually between 15 and 45 mg; the starting dose is 15 or 30 mg. Mirtazapine begins to exert its effect in general after 1-2 weeks of treatment. Film-coated tablet. Mirtazapine 15 mg Tablets are yellow, oblong and biconvex tablets with a score line on one side. Side Effects. See also the Warning section. Dizziness, drowsiness, lightheadedness, increased appetite, weight gain, dry mouth, or constipation may occur. How to take mirtazapine. Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. The manufacturer's leaflet will give you more information about mirtazapine and a full list of side-effects which you may experience from taking it. Mirtazapine (Remeron, Remeron SolTab) is an oral medication used to treat depression. Learn about side effects, warnings, dosage, and more.