Brief Answer:
Medications > SOD, sphincterotomy

Detailed Answer:
thank you for asking!
i believe the medicines you use both zopiclone and sertraline are notorious for weight gain.And need to be used to minimum or better stopped.
Now the sphincter of oddi dysfunction may reduce the weight but weight gain has never been correlated yet with it. I am sure you must have been evaluated on XXXXXXX protocol and your liver enzymes must be raised with dilated bile duct on ERCP.Well the management of that SOD is very simple. SPhincterotomy followed antispasmodics and avoidance of opioids analgesics and sedatives because both of them cause Sphincter of oddi dysfunction.
Rest as far as weight gain is concerned, 7 kg can be easily lost with a good healthy lifestyle and exercise.
Let me explain weight losing guidelines to you.
A good start is always a modification in diet and lifestyle. self monitoring of caloric intake, stimulus control, non food rewards, relapse prevention, seeking dietitian help etc.

Sign up to a weight loss program under an FDA approved clinician with realistic goals and expectations regarding weight loss.
I call them SMART: Specific, Measurable, Attainable, Realistic, and Timely.Before signing up to programs evaluation for psychiatric morbidities is a must do procedure to sort out depression, eating disorders, not complying will lead to drastic effects and changes in lifestyle and personality which one would regret for long time.

Now what should be the goal and target? it is usually recommended to lose weight at a pace of 1-2 pounds per week and faster than this can lead to issues inevitable. maximum of 10 % of the weight or more precise 30 pounds is to be reduced in one program on 12 weeks maximum followed by a break with try to maintain the loss for at least a year and then trying further.

Remember losing weight is easy. maintaining the loss is a challenge. and to do that one needs self monitoring of weight, low fat diet intake, daily exercise of at least 60 minutes with no breaks, minimum sedentary time in life like watching TV or bed ridden habits. Diet induced weight loss increases the hunger and appetite and creates a challenge for the patient and the perseverance and patience is tested otherwise rep lapse occurs and all effort goes in vane. And this applies to every age group but children more specific as their lifespan matters the most here.

Energy expenditures are obsolete these days as metabolism varies, usually 22 kilo calories are required for every kg to be maintained therefore weight loss reduces the expenditure and dampen the pace of loss which most of the time disappoints the patient and then they commit the cheap publicity damaging stunts to be a super man in one day , time when they lose it.Also every decade / 10 years reduce the 100kcals consumption in a body so old people need more effort to lose the same weight as does the adult does , men lose more than women at the same effort.

What to eat, what not to eat how to eat how much to eat and when to eat are some very import an questions need to be answered.

Low fat diets like Ornish diets, Low carbohydrate diets like Atkin diets and Medievel diets like zone diets in which all three major nutrients of carbohydrates, fats and proteins are used in equal proportion , JOLSIN WHY WAIT diet for diabetic patients( 40-65 % carbohydrates, 20-30 % fats and less than 35 % fats) are some of the diets clinicians recommend for obesity.
these are balanced. low calories and reduced-portion sized diets recommended by dieticians
portion control can be attained by getting involved in weight loss programs like XXXXXXX XXXXXXX Nutrisystem or by the use of products such as meal-replacement shakes, bars, prepackaged meals, and frozen entrees (eg, Slim-Fast, Glucerna, Lean Cuisine, Healthy Choice, Smart Ones). These have adequate and enough amounts of the major diet components based on the food pyramid from the US Department of Agriculture and recommended daily allowances (RDAs). These sources also have adequate micro components of nutrition and trace elements like vitamins and minerals etc.
Alcohol, sodas, most fruit juices, and highly concentrated sweets are generally calorie dense and nutrient deficient (so-called empty calories). therefore, these are generally prohibited and to be avoided or reduced to a minimum levels of possible.
If you keep the calories intake in the range of 500-1000 kcal/ day ro 800-1800 kcal/day , you will start losing weight at a pace of 1-2 pounds ( 0.4-0.5 kg) every week. ideal loss in 10 – 20 pounds for 200 pounds person over 3- 6 months.
if you try more faster than this you will develop complications like Vitamin deficiency, starvation ketosis, electrolyte derangements and gall bladder stones etc are some amongst them. keep preteens in range of .8 to 1.5 per kg do not exceed 100 gm. carbohydrates maximum 50 gram per day, water drinking of more than 1000 ml or minimum of 6 glasses,
it is said that drinking cold water 10ml per kg ( e.g. 700 ml / 3 glasses for 70 kg man) before every meal accelerates thew weight loss and makes it easy. so make a habit of drinking water before meal.
Last but not the least way is exercise. Intensive exercise programs work like charm but cardiac and respiratory profiles need to be evaluated first before prescribing them. Aerobic isotonic exercises are the best amongst all. Ideal is 30 – 60 minutes a day 5 – 7 imps a week. Anaerobic isometric exercises, resistant training can be used as side technique but with a lot of monitoring.
Modify behaviour before its to late, never sleep for more than 7 to 8 hours..sleeping less than 6 and more than 9 hours are both lethal and a great addition to obesity. so balance of sleep is advised and any extreme would exaggerate the obesity issue.
Now the list of medications prescribed in obesity but to be used only after consulting a physicians and let them choose what is best.
Lorcaserin Belviq
Phentermine/topiramate (Qsymia)
Phentermine (Adipex-p, Ionamin, Suprenza)
Diethylpropion (Tenuate, Tenuate Dospan)
Phendimetrazine (Bontril,Bontril PDM, Adphen, Aplhazine,Phenazine )
Benzphetamines (Didrex)
Orlistat (Xenical, Alli)

There are many products like above mentioned available over the counter with out prescription like ephedrine, caffeine, benzocaine, chromium, psyllium, chitosan, and herbal preparations. Herbal ingredients frequently include ma huang (Ephedra sinica), St. John’s wort (Hypericum perforatum), guarana (Paulinia cupana), kola nut (Cola nitida, Cola acuminata, and Garcinia cola), hydroxycitric acid (Garcinia cambogia) etc.
Bariatric Surgeries are new development and advised to BMIs above 40 or people in old age where exercise is not an option for weight loss

I hope it helps. Take good care and don't forget to close the dysfunction please.
Regards
S Khan

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Brief Answer:
No worries for weight, bupropion and TCA

Detailed Answer:
Thank you for asking!
Now that you mentioned your weight of just 68 i am sure it is not that much to worry about. even a height of 5 feet 3 inches and above can justify that.
So stop worrying for that. Yes both of them cause weight gain one more than the other. Almost all antidepressants cause weight gain some more than the other. According to the study by FDA , it was shown that bupropion and the tricyclic antidepressants nortriptyline and amitriptyline were associated with less weight gain and same holds true to my personal practice.
Get to your psychiatrist and let them decide what is best for you. And continue using low fat diets and all the diet plans i mentioned. Seek a dietitian and let them help you devise a plan.
take care and dont forget to close the discussion please.
Regards
Khan

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