Tummy tuck scar looks dark purple. Is it normal for the incision to look dark purple ?

With due respect to Mr. Ross, this is not "normal" and does not look fine. This does not appear to simply be scabbing, but patchy discoloration of the skin itself adjacent to the actual incision edges centrally above the pubis.

Purple/black in this pattern is a clear sign of localized ischemia (poor circulation) near the margin of your skin incision. Note this is near the center of the incision (where circulation is most impaired) and not at the ends, where the microcirculation is better. If you are a smoker, or even exposed to second-hand smoke, nicotine can cause damaging vasoconstriction and must be stopped immediately.

But even without nicotine exposure of any kind, inadequate circulation leading to dead skin or fat necrosis can still occur in a small percentage of patients. What is dead cannot be revived, but what is marginal can (sometimes) be improved by a number of means. You need to know that although this is not "normal," neither does it signify that anything was done wrong or inadequately. You should see your surgeon immediately and let him/her know of this appearance and receive an examination and advice. In some cases this will go on to heal adequately, though with some increased scarring. In other cases this can lead to wound breakdown, so this is nothing to be ignored without at least careful observation and follow-up.

I would also consider nitro paste (a vasodilator), though this is controversial. But if it can help, why not? Again, avoid all nicotine. Best wishes! Dr. Tholen

It may take several
months for a tummy tuck patient’s scars to soften, for sensation to return, and
for relaxing of the tight sensation in the abdomen. In the case of extensive
surgery, abdominoplasty recovery can be uncomfortable and may take longer. Scars
may stay red, become thick or widen. It can take 12-18 months for the scars to
settle.

These can be improved
with topical treatments such as BioCorneum, Scar Guard, Scar Fade and Mederma.
Redness can be improved with laser treatments and the scars can be kept narrow
with products such as Embrace.  On
occasion, keloids or hypertrophic scars can develop and will need treatment
including Kenalog, 5FU and laser.

While you are concerned with the healing of your incision it is best to visit your surgeon and have the area examined to make sure that healing is progressing well. Good luck.

It is always difficult to comment without a physical examination and you are best to be examined in person by your PS.The colour of the scar itself looks fine and normally looks purple / black. There is some discoluration above the scar and it is unclear whether this is bruising or not. Keep in touch with your PS and best if he/she sees the pics and best if all he/she examines you personally.