weight loss medications

Weight Loss Medications to Lose Weight: Are They Right For You?

September 25, 2017

Weight loss medications can be a great tool for patients prior to and after weight loss surgery. Medications may be prescribed before surgery if patients are required to lose weight and have been struggling to do so on their own. Often times, taking medication for only a few months can result in adequate weight loss in preparation for surgery.

Weight loss medications are safe to take after surgery. Weight loss medication is not intended for patients looking to lose beyond their target weight after surgery. Even for patients who have undergone weight loss surgery many years ago may find medications helpful in getting back on track and enabling them to start losing again.

There are times when patients are unable to have weight loss surgery for reasons such as insurance, prior surgeries, health or personal reasons. For these patients, weight loss medications may be a good option.  They can provide patients with the help they may need in losing weight than diet and exercise alone.

Deciding which weight loss medication is right for you can be overwhelming. Multiple studies have shown losing 5-10% of your body weight can have a positive impact on health issues such as heart disease, diabetes, cholesterol and joint problems. The FDA (Food and Drug Administration) has currently approved five weight loss medications, which are available with a prescription.

There are risks and benefits to each medication and it is important that you review your medical history and current medications with your provider prior to starting any new medications.  As with any weight loss program, it is key that you are making changes in your diet and exercise to see the best results.

To qualify for weight loss medication, your BMI must be equal to or greater than 27 with at least one health issue such as high blood pressure, obstructive sleep apnea, high cholesterol or diabetes.  If your BMI is greater or equal to 30 you do not need any other health issues to qualify.

At 12 to 16 weeks after starting a weight loss medication if you have not lost 4-5% of your starting total body weight the medication will be stopped by your provider as there is no benefit to continuing.  All weight loss medications cannot be taken during pregnancy. Some providers may require monthly pregnancy tests.

Five Prescription Weight Loss Medications

Below is a review of the five weight loss medications currently available by prescription and approved by the FDA. The charts will better help you to understand each medication.


Dosing One 20 mg Extended Release Tablet daily or one 10 mg tablet twice daily
How it Works Belviq affects 5-HT 2c receptors which are believed to decrease food consumption and promotes the feeling of fullness.
Study Results On average patients lose 5% or more of their body weight. It has also been shown to improve A1C and fasting blood sugars in patients with type 2 diabetes.
Side effects Headache, dizziness, fatigue, nausea, dry mouth, and constipation.
Caution Patients taking SSRI, SNRI, Bupropion, Tramadol, and Antipsychotics, taken together with Belviq can cause Serotonin Syndrome. This is when you can have too much Serotonin in the body causing mild symptoms such as diarrhea, nausea, vomiting to severe symptoms such as coma or hallucinations. Patients with valvular heart disease or Congestive Heart Failure (CHF). In patients with type 2 diabetes, weight loss may cause low blood sugar so it is important that you are checking your blood sugar and following up with your provider to adjust diabetes medications as needed.


Dosing Dose increased over a four week period. Week 1, one tablet in the morning. Week 2, one tablet in the morning, one tablet in the evening. Week 3, two tablets in the morning and one tablet in the evening. Week 4 two tablets in the morning and two tablets in the evening. Week 4 and beyond is the maintenance dose of two tablets twice daily.
How it Works A combination pill that contains Wellbutrin and Naltrexone. The combination of these two medications reduces hunger and decreases cravings.
Study Results Patients lose 2-4 times more weight than patients who diet and exercise alone.
Side effects Nausea, constipation, headache, vomiting, dizziness, insomnia, dry mouth and diarrhea.
Do not take Uncontrolled high blood pressure, seizure disorder, or patients who are taking chronic opioids (oxycodone, hydrocodone, tramadol, or methadone).
Caution May increase the risk of suicide.

Dosing The first two weeks are a lower starting dose taken once daily in the morning. At week 3 the maintenance dose is started and taken once daily in the morning. Higher doses are available if your provider feels this is necessary.
How it Works A combination pill consisting of Phentermine and Topiramate. This combination works by reducing your appetite and helping you to feel fuller.
Study Results Patients lose up to 10% on average of their body weight at one year.
Side effects Tingling or prickling like pins and needles (of the hand, feet and face), dizziness, metallic taste, insomnia, constipation and dry mouth.
Do not take Glaucoma, hyperthyroidism, patients taking a class of antidepressants called MAOIs.
Caution It may increase your heart rate, making it important that you are following up with your doctor regularly for monitoring. Let your doctor know right away if you have heart palpitations.

Dosing Available in 8 mg, 15 mg, 30 mg and 37.5 mg. The 8 mg dose can be taken three times a day. The higher doses should be taken earlier in the day as it can affect sleep. The duration of treatment tends to be around 3 months as the effectiveness of the medication will decrease after this time.
How it Works Decreases appetite and increases many patients energy level.
Side effects Constipation, diarrhea, dizziness, dry mouth, headache, insomnia, mood changes, nausea or vomiting, rapid heartbeat, stomach pain, tiredness, and unpleasant taste.
Do not take History of cardiovascular disease which includes stroke, heart attack, heart failure, uncontrolled high blood pressure, glaucoma, history of drug abuse, and agitated states.
Caution As noted with Qsymia, phentermine may cause an increase in heart rate. So it is important you are following up with your provider for regular follow ups and alerting them if you are having chest pain or palpitations.

Dosing Once daily injection. The dose is increased (titrated up) over 4 weeks.
How it Works Works like a hormone in your body so you feel less hungry.
Study Results One study showed 3 out of 5 participants lost 5% or greater of their body weight and 1 out of 3 patients lost 10% of their body weight.
Side effects Nausea, diarrhea, constipation, vomiting, headache, fatigue, dizziness, and abdominal pain. Serious side effects include pancreatitis, increased heart rate, kidney failure and possible thyroid tumors.
Do not take If you or a family member have a history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2 (MEN 2).
Caution You cannot take Saxenda with Victoza, as they have the same active ingredient.

With the variety of weight loss medications currently available there is usually something for many patients. Have an open conversation with your provider about what you hope to achieve. As part of a healthy diet and exercise regimen weight loss medication can be another tool to help you succeed in weight loss.



Rachel Tierney is a Certified Physician Assistant. Rachel works for Saratoga Bariatric Surgery and Weight-Loss Program in Saratoga Springs, NY with Dr. Dmitri Baranov. Rachel assists Dr. Baranov in the operating room and sees patients in the inpatient and outpatient setting and has been in the field of bariatric surgery taking care of WLS patients since 2010.

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