Neurotoxin injected into the gastrocnemius to reduce muscular calf bulk. Performed personally by Dr. Amir Mortazavi, MD.

The gastrocnemius is the large superficial calf muscle that creates the visible bulge along the back of the lower leg. When it's overdeveloped — from genetics, running, dance, years in heels, or sport — it widens the calf and makes the lower leg look shorter and heavier than the rest of the body.

Partially relaxing it allows the muscle to reduce in size over subsequent weeks, narrowing the calf and lengthening the visual line of the leg.

This is the most established of the body-slimming neurotoxin treatments after masseter. It has been performed widely for years, particularly in East Asian aesthetic practice where calf contour is a common concern, and there is a meaningful body of clinical experience behind it.

Is your calf muscular or is it fat?

This is the question that determines whether the treatment will do anything, and it's easy to check yourself. Stand up and rise onto your toes. Watch the back of your calf.

A distinct bulge appears and hardens → the bulk is muscular, and neurotoxin can reduce it.

The calf stays soft and doesn't change shape much → the bulk is subcutaneous fat, and neurotoxin will do nothing for it.

Most calves are some of both. Dr. Mortazavi assesses the ratio at consultation, because a patient whose calf is mostly fat will get no result from this treatment and should be told so before booking rather than after.

What to expect: treatment takes about 20 minutes. Onset is gradual — softening begins around two weeks, with visible slimming developing over one to three months as the muscle reduces. Duration is typically four to six months, often longer than facial treatment. With repeated treatment, many patients find results last progressively longer as the muscle stays reduced.

Walking, standing, and daily activity are unaffected at appropriate dosing. The gastrocnemius shares its work with the soleus and other lower leg muscles, which compensate. Some patients notice mild fatigue with prolonged running or stair climbing in the first few weeks.

Not appropriate if you're a competitive runner, dancer, or athlete whose performance depends on explosive calf function, or if your calf bulk is primarily fat rather than muscle.

Realistic expectation: this narrows a muscular calf. It doesn't change bone structure, ankle definition, or overall leg length. Patients expecting a transformation of the entire lower leg will be disappointed by a result that worked exactly as intended.