"Even as a pigtailed child Ashley Gallagher was selfconscious about a certain fullness in her face. I was cute as button  and there was my double chin she said. As an adult she faithfully performed facial exercises purported to tighten the area under the chin. She stood ramrodstraight head held high to make the bulge less apparent. Nothing worked. By middle age Ms. Gallagher  the owner of a petsitting business in Torrance Calif. was avoiding mirrors and considering liposuction httphealth.nytimes.comhealthguidessurgeryliposuctionoverview.htmlinlinenytclassifier but she worried about the effects of anesthesia httptopics.nytimes.comtopnewshealthdiseasesconditionsandhealthtopicsanesthesiaandanestheticsindex.htmlinlinenytclassifier and the recovery time. Then she discovered another option a series of fatreducing injections intended to slim down a double chin. She enrolled in a trial and by the third treatment session I noticed a dramatic difference she said. It was receding. The Food and Drug Administration httptopics.nytimes.comtopreferencetimestopicsorganizationsffood_and_drug_administrationindex.htmlinlinenytorg on Wednesday approved the injection http called Kybella for the reduction of moderate to severe fat deposits under the chin. The active ingredient deoxycholic acid dissolves fat permitting dermatologists and plastic surgeons to resculpt the chin area without surgery. For highly selected patients who have underchin fat without sagging skin this will work said Dr. Rod J. Rohrich a professor of plastic surgery httptopics.nytimes.comtopnewshealthdiseasesconditionsandhealthtopicsplasticsurgeryindex.htmlinlinenytclassifier at the University of Texas Southwestern Medical Center in Dallas. He was not involved in the clinical trials. Dr. Rohrich editor in chief of the journal Plastic and Reconstructive Surgery predicted that both men and women would want the procedure. So many consumers dont want a knife they want a needle he said. Men in particular are not inclined to undergo cosmetic procedures that require long recovery he said but might be tempted by minimally invasive treatments in a doctors office. We are basically wimps Dr. Rohrich said. Tiny needles containing deoxycholic acid  up to  per session  are inserted into the fat deposits under the jawline. Treatment entails two to six monthly sessions of roughly  minutes each. Patients must commit to multiple visits. In studies conducted for F.D.A. approval the most commonly reported side effects were bruising pain and swelling. Dr. Derek H. Jones a dermatologist and a principal investigator in a trial of the drugs effectiveness found that people with the most fat had the most swelling. It usually cleared up in  to  hours. That makes sense because youre destroying more fat cells said Dr. Jones a paid consultant who will teach injectors and who treated Ms. Gallagher. In his experience the first treatment is the most painful. The injections will be commercially available in late summer after doctors are trained to give them. The price for Kybella is not yet set. Not every patient is a good candidate for this treatment several experts said. If a patient has excess fat and loose skin Dr. Rohrich said youll have a crepey neck and need a neck lift after fat is reduced with the shot. Neck lifts can cost  or more. Ms. Gallagher before the injections to slim down her double chin. The drug does not target only fat cells. It will also destroy skin cells if inadvertently injected into the skin the F.D.A. has warned. If you inject into the dermis you can hurt the skin Dr. Rohrich said. This drug needs to go into fat tissue to work. Misdirected injections could even harden skin he said. Kythera Biopharmaceuticals http conducted two randomized trials to assess the efficacy of Kybella. More than  patients at  sites in the United States and Canada participated. The pooled results from both trials found that . percent of patients who got the drug saw at least a onegrade reduction in fat compared with . percent of patients who got sham injections. Grading was determined by clinical examination and answers on a standardized form. Sixteen percent of patients who received the real injections saw a reduction of two grades in underchin fat. Only . percent of the placebo group saw that level of improvement. M.R.I. httphealth.nytimes.comhealthguidestestmrioverview.htmlinlinenytclassifier scans also showed that underchin volume had decreased more in treated patients than in ones who received placebos. Dr. Lynn A. Drake a dermatologist and lecturer at Harvard Medical School was the chairwoman of the F.D.A. advisory committee that unanimously voted in favor of approval in March. The benefits outweigh the risks said Dr. Drake who does not speak on behalf of the F.D.A. Still she cautioned patients will need to choose a welltrained doctor for the procedures. When people put needles around your face it has so many important structures that could be accidentally or inadvertently hit she said. In studies of the injection facial nerves were accidentally injured in . percent of patients leaving them with asymmetrical smiles for  days on average. Roughly  percent suffered swallowing problems for a few days. The F.D.A. warned against injecting Kybella into parts of the body other than the chin area http saying that it is not known whether this use is safe or effective. Patients should also make sure your physician is using the real product advised Dr. Heidi Waldorf a paid principal investigator for Kythera and a cosmetic dermatologist in Manhattan. Compounded antifat injections are not approved by the F.D.A. and have caused serious side effects in the past http Ms. Gallaghers results have lasted three years. Even though she went up a size in jeans she said its not showing up in my face. She is newly single but she is approaching the dating scene with newfound verve. Theres definitely an increase in confidence so Lord help them she said referring to potential dates. Im done worrying about my insecurities."