Is Cephalexin Strong Enough to Clear Infection in Breast Implant?

Thanks for the question.
Implants are not part of your body's natural tissue and can be more prone to infection and less able to clear infections compared to your natural tissue.
Some doctors will typically use Keflex (cephalexin) in all post-operative cases to reduce the chance of infection. Technique during surgery is even more important, including irrigation of the pocket with triple antibiotic irrigation solution, minimal handling of the implant and meticulous closure.
I have treated patients with implant infections (fortunately none of my own). Treatment can include oral antibiotics. Many times, if I truly suspect an infection, IV antibiotics may be required as aggressive treatment can be required. Part of the evaluation may include physical exam and history as well as lab work (checking your white count).
Sometimes an infected implant is not salvageable and must be removed. Also, infection can be associated with capsular contracture in the future.
Be sure to stay in close communication with your surgeon. Report any changes including fever, increased redness (many times marking the redness with a felt tip pen can be a good way to track whether it is getting larger or smaller) or drainage.
I hope this helps!

Cellulitis after breast augmentation is a reason to be concerned and your plastic surgeon is acting appropriately. Although the surgeons here can all conjecture on the course of management, only the plastic surgeon who saw you in consultation can assess whether this is  fulminant cellulitis or erythema.  I would follow up with your surgeon.

Without a culture of the infection, your surgeon has to choose an antibiotic empirically.  Keflex is a suitable choice and it is as "strong" as any antibiotic.  Whether it covers the specific bacteria that is causing your infection is uncertain but it probably does.  The problem for you is that if you indeed have and infection, even if Keflex clears it up, the likelihood of a capsular contracture in the future is very high.

Keflex is a commonly used antibiotic to prevent infection known as prophylaxis. If your surgeon is concerned about an early infection another course of antibiotic is reasonable as is close surveillance. Personally, I would use a antibiotic that is more effective for the organisms most commonly the cause of implant/wound infections. Spectrum ( range of bacteria the drug effects) is how we choose a drug, it has nothing to do with strength. I may chose a broader spectrum drug such as augmentin, cipro with or without Bactrim. If this is an early infection, it needs to be treated early on or else it can progress to the point where the device may have to be removed. This, however, is extremely rare!

It sounds like your surgeon is being appropriately cautious, and anything that might be going on is a relatively minor problem, or you would be experiencing more remarkable symptoms.
In other words, when implants get infected, because they don't have an immune system or their own blood flow, the infection usually progresses rapidly. This causes rapidly worsening fever, chills, swelling, redness, pain, and often drainage and failure of the incision to heal. It is not subtle.
So, if all you are experiencing is a bit of redness in the skin, but otherwise are doing well (some minor asymmetry in swelling is common early after surgery), I would take the antibiotic prescribed and keep all of your follow up appointments, anticipating a smooth recovery.
If anything seems to be getting worse over time rather than better, call your surgeon immediately for re-evaluation.
Congratulations on your new breast contour!

Your doctor maybe overly cautious. Having an overt infection in the breast after an augmentation is fairly rare. So the Cephalexin or Keflex is likely fine. You will just have to keep an eye on it and if you start having pain, worseing redness, not feeling generally well or fevers then contact your plastic surgeon immediately.

Hope that helps.