Brief Answer:
It can last some days.It don't need any treatment.

Detailed Answer:
Hello!
I am Dr.Rovena
I had gone through your query and medical history.

It is vary common that after taking antibiotics( especially if this lasts more than 10 days) to experience diarrhea.
Antibiotic-associated diarrhea occurs when antibiotics upset the balance of good and bad bacteria in your gastrointestinal tract.

Your digestive tract is a complex ecosystem that's home to millions of microorganisms (intestinal flora), including hundreds of species of bacteria. Many of these bacteria are beneficial, performing essential functions.
But some of the bacteria that normally inhabit your intestinal tract are potentially dangerous. These harmful bacteria are usually kept in check by beneficial bacteria unless the delicate balance between the two is disturbed by illness, medications or other factors.

Antibiotics kill these “good” microbes along with bacteria that are causing an infection. This upsets the balance of the normal flora in the intestines. The result is often loose, watery stools known as antibiotic-associated diarrhea.

Most often, antibiotic-associated diarrhea is mild and clears up shortly after you stop taking the antibiotic.
Mild antibiotic-associated diarrhea may not require treatment.

So if you are experiencing only diarrhea,without any other symptom such as severe abdominal pain,fever,blood in stools You don't need to worry.
This diarrhea will clear up in some days and you don't need any other treatment.

During this time be careful with dehydration Try following this tips:

-Drink more water and other liquids to replace fluids lost because of diarrhea.
-Eat soft, bland foods and avoid spicy or greasy foods that can aggravate diarrhea.
-Eat several small meals, rather than a few larger meals.

You also can take Probiotics which are organisms, such as bacteria and yeast, that can help restore a healthy balance to the intestinal tract by boosting the level of good bacteria to help defeat the harmful bacteria.
Probiotics are available in capsule or liquid form and are also added to some foods, such as certain brands of yogurt.

If you start feeling abdominal pain,fever,blood in stools,very dry mouth, intense thirst, little or no urination, and extreme weakness than you should seek medical help because a complication might have happen such as an infection of Closstridium difficile which need immediate treatment.

Hope I was able to help.If you have any further questions I will be happy to help.
Wish a quick and complete recovery.
Dr.Rovena

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