Chapter 21. Western Medicine Therapy: Classification and Key Points of Appetite Suppressants

XI. Western Medicine Therapy

Generally, most people with mild, moderate, or even severe obesity can achieve weight loss through diet control and increased physical exercise. If these measures are ineffective, medication can be considered as an adjunct therapy. However, medication is not a primary treatment for obesity because the mechanisms of obesity are not yet fully understood, and therefore, no truly effective drugs have been found. This chapter's discussion of drug-based weight loss refers to the use of Western medicine for weight loss treatment. Some physicians advocate against prescribing any medication, arguing that medication for obesity can lead to unrealistic expectations, causing patients to place their hopes on drugs and neglect dietary management, changes in eating habits, and abandonment of exercise. However, current research shows that a significant proportion of people who participate in diet and exercise for weight loss experience ineffective results or, even if initially effective, experience weight rebound. Therefore, we believe that necessary medication can serve as an adjunct to diet and exercise therapy to encourage long-term adherence. For some patients with refractory obesity, drug-based weight loss methods can be explored.

Readers are reminded here that weight-loss medications should only be taken under the guidance of a physician. This book provides a brief introduction to weight-loss medications to give readers a comprehensive understanding of methods, but readers should not self-medicate. Western weight-loss drugs often have side effects and should not be used as a first-line or long-term treatment; they should be taken under the guidance of a physician.

Currently, the most commonly used weight-loss drugs in China fall into four main categories.

(a) Appetite suppressants

These medications work by stimulating the hypothalamic satiety center and inhibiting the appetite center, thus suppressing appetite through neural action and making it easier for obese individuals to control their appetite. Common side effects of this group of drugs include insomnia, rapid heartbeat, high blood pressure, sweating, dizziness, vertigo, nausea, vomiting, and constipation. Fluamphenicol and fluoroquinolone esters are considered better in this group, exhibiting stronger effects with fewer side effects. They are contraindicated in patients with hyperthyroidism, glaucoma, or severe hypertension.

1. Amphetamine

Amphetamine, also known as benzedrine or phenamine, is taken orally at a dose of 5–10 mg, 2–3 times daily.

2. Dextrorotatory amphetamine

Dextroamphetamine, also known as dexamine or dexedrine, has an appetite-suppressing effect twice as strong as amphetamine. The dosage is 2.5–5 mg orally, 2–3 times daily. Long-acting capsules are available, each containing 15 mg, taken once in the morning.

3. Benzyltoluene

Benzphetamine, also known as didrex, is suitable for obese people with diabetes. The dosage is 25-50 mg, 1-3 times a day, taken orally before noon.

4. Fluoroamphenicol

Fenfluramine, also known as obedrex, ponderax, or pondimin, has an appetite-suppressing effect 8-10 times stronger than amphetamine. It has minimal side effects such as increased blood pressure and insomnia, and possesses a calming effect. It is suitable for patients with cardiovascular disease, hypertension, and anxiety. The dosage is 20 mg orally, 2-3 times daily, gradually increasing to a maximum dose of 100-200 mg/day.

5. Nicotinamide

Phenarme, also known as fenutin or periton, can lower blood pressure and is suitable for people with hypertension and obesity. The dosage is 50-150 mg orally, 2-3 times daily. It can relieve fatigue and produce euphoria, but is easily addictive and can lead to psychological dependence.

6. Chlorpheniramine

Chlorphentermine, also known as avicol or desopimon, has a strong lipid-lowering effect and is suitable for obese individuals with hyperlipidemia. The dosage is 25 mg orally, 2-3 times daily.

7. Fluoropropylamine ester

Fluoropropylamine ester (S992) has the same effect as fluoropropylamine but is less toxic. Dosage: 150–600 mg, daily dose, divided into several oral doses.

(ii) Biguanides

These medications are more suitable for obese patients with diabetes. They do not lower blood sugar in obese patients without diabetes, so they can also take them. Under the same dietary control conditions, those taking this medication experience 20% more weight loss than those not taking it, and this type of medication can help 80%–90% of obese patients achieve weight loss. Reports indicate an average weight loss of 3–3.5 kg over 6 months. However, prolonged treatment weakens the effect. Weight loss may stop after 12 weeks. A treatment method of taking the medication for 3 months and then stopping for 2 months can achieve satisfactory results.

1. Benzoguanidine

Benzophenformin (Dapoxetine), orally, start with 50 mg twice a day, then increase by 50 mg weekly until gastrointestinal irritation symptoms occur or the dose reaches 300 mg/day.

2. Metformin

Metformin (a hypoglycemic agent), orally, starting with 500 mg twice daily. Increase by 500 mg weekly until gastrointestinal symptoms occur or the dosage reaches 3000 mg/day.