Obesity itself is the cause and house for many diseases.Generally obesity should not be treated with drugs unless the situation is not controlled by normal dietary and exercises activities.So if in case obesity is becoming a problem then these drugs can be used according to the condition.
Talking about normal body functions, the Nor adrenaline decreases appetite and Serotonin induces satiety.
Some of the anti obesity drugs are:-
•Phenyl propanolamine– It is adrenergic drug.The risk of using this drug is that the patient with HTN may have hemorrhagic stroke.So many countries have banned this drug and is not used much in other countries.But this drug have anti obesity action by acting on appetite centre.
•Amphetamine- This is adrenergic drug which have great effect on brain, it stimulates the brain gives relief to the patient and so was misused by many.Amphetamine nowadays is used for Narcolepsy.But the adverse effect with drug is of Tachycardia,Tremor, Tachyphylaxis and constipation.
Tachyphylaxis means rapidly diminishing effectiveness of the drug i e if initially 5mg of drug was very effective in the patient but after sometime it is having no effect and we have to increase the dosage of drug.
•Fenfluramine- This drug have serotonergic action i.e it stimulates serotonin and induces satiety and so it is used as anti obesity drug.It have A/E of Diarrhoea,Night mares, Drowsiness and is banned due to some cases of damage to lungs/heart.
•Dexfenfluramine- It is also serotonergic drug but is more safer than the previous Fenfluramine drug.
•Sibutramine- It have both Serotonergic action + adrenergic action as well so is much better drug.But it is also banned due to some cardiovascular related risks
•Orlistat- It is a lipase inhibitor. So it causes less digestion and absorption of fat (helpful as anti obesity drug) from the intestinal walls and so fat will be passed out with faeces causing steatorrhea.
(There are other drugs also but the basic idea and pharmacodynamics is same as of the drugs which are explained here.)
Because of the potential side effects of these drugs and small benefits in weight reduction these anti obesity drugs are not used much,they are prescribed only in the case when obesity becomes a serious problem and the treatment overweighs the side effects of these drugs.
Contributor- Medico Anant Singh Nanda
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