Mechanism of Action of Salivary Gland Botox

1️⃣ Basic Mechanism – Acetylcholine Blockade

Botulinum toxin blocks the release of acetylcholine at the nerve endings.

Normally, in the salivary glands:

Parasympathetic nerve activation

Acetylcholine secretion

Salivary gland cell stimulation

Increased saliva production

This is the standard process.

When Botox is injected:

→ Acetylcholine secretion is blocked

→ Salivary gland cell stimulation decreases

→ Saliva production decreases

This sequence of events occurs.

2️⃣ Suppression of Salivary Gland Function

The parotid gland is composed of serous acini structures.

When acetylcholine is reduced:

Decreased release of secretory granules

Decreased fluid movement

Decreased saliva production

As a result, the function of the salivary gland is suppressed.

3️⃣ Reduction in Salivary Gland Size (Atrophy)

When the salivary gland is used less:

Decreased cellular activity

Acinar cell shrinkage

Decreased glandular volume occurs.

In other words, functional decline leads to structural shrinkage.

Therefore, this results in:

Reduced facial width

A slimmer lower face.

4️⃣ Functional Recovery After Nerve Regeneration

This is why the effects of botulinum toxin are not permanent.

Over time:

SNARE protein regeneration

Nerve terminal recovery

Recovery of acetylcholine secretion

As these occur, salivary gland function returns.

Thus, the effects typically last for 3 to 6 months.

5️⃣ Changes Confirmed in Studies

Decreased saliva production

Decreased salivary gland thickness

Decreased facial width

In particular, the most significant reduction is often seen between 6 to 8 weeks.

6️⃣ Why Does the Salivary Gland Shrink? (Core Concept)

Functional suppression

→ Decreased saliva production

Decreased usage

→ Tissue atrophy

These two processes combine to reduce the size of the salivary gland.