ODT/RDT vs. Troche: Maximizing Oral Drug Absorption

Two Ways to Take Sublingual Ketamine

When ketamine is prescribed for at-home therapy, it's typically formulated as either a rapidly dissolving tablet (RDT/ODT) or a troche (lozenge). Both deliver the medication through the oral mucosa, bypassing the digestive system for better absorption. But the patient experience and pharmacokinetics differ.

Rapidly Dissolving Tablets (RDTs/ODTs)

RDTs disintegrate within seconds on contact with saliva. No water required.

Advantages:

• Fast dissolution — Breaks down quickly, allowing rapid mucosal absorption
• Ease of use — Simple and familiar; similar to taking any tablet
• Better compliance — The quick dissolve time makes the experience less unpleasant
• Improved bioavailability — Less medication is swallowed, meaning more reaches the bloodstream through the oral tissue

Considerations:

• Less control over absorption timing
• Saliva accumulation may lead to some unintentional swallowing
• More complex and costly to manufacture

Troches (Lozenges)

Troches are waxy, candy-like lozenges that dissolve slowly when held in the mouth.

Advantages:

• Controlled release — Slower, more gradual drug delivery
• Localized contact — Extended time against the oral mucosa
• Established formulation — Widely available from compounding pharmacies

Considerations:

• Slower onset of action compared to RDTs
• Many patients find the texture and taste unpleasant
• Extended dissolution time can reduce compliance
• Require refrigeration — Heat-sensitive
• Longer hold time in the mouth can cause more salivation and swallowing

Which Is Better?

Neither formulation is universally superior. The choice depends on patient preference, provider recommendation, and individual response.

At Discreet Ketamine, we primarily use orally disintegrating tablets because they offer a better patient experience — faster dissolution, less unpleasant taste, and more consistent absorption.

An Important Note on Quality

Both formulations come from compounding pharmacies, meaning they're subject to the individual protocols and practices of each pharmacy rather than standardized pharmaceutical manufacturing. This can create variability in potency and formulation quality.

This is why working with a provider who has established relationships with reputable compounding pharmacies matters. Quality control isn't something patients should have to worry about.

For a broader comparison of all ketamine delivery methods, see all the ways ketamine can be given. For details on how sublingual compares to IV, see our dedicated comparison guide.