Brief answer....very frankly speaking,There is no allopathic medicine which can increase the breast size.
Detailed answer....
Hello,
Thanks for the query.
Very frankly speaking there is no allopathic medicine which can augment the breast size,however there are ways by which it can be achieved by .....
Doing regular exercises like push ups and isometric chest contractions
Eating well 
Eating foods like soy cheese,soy milk,tofu etc which have natural estrogens and phytonutrients.
Consuming herbs like fennel,fenugreek and saw palmetto,however all these methods don't provide any surety of the outcome.
And lastly 
One can opt for breast implants,if other employed methods fail or if somebody wants quicker results.
I hope it helps,however you may revert to me for any further query.
Best of luck
Thanks

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