Question

If the troches end up convex, what is the best way to make then pharmaceutically elegant?
Use a heat gun to heat them up and smooth with a spatula.
Pour more liquid base into the troches with a convex shape.
Just leave the troches as is.

Answer 1

Short answer: neither “blast with a heat gun and spatula” nor “top up with more base” are ideal. Either leave them if the convexity is purely cosmetic and pharmacopeial specifications (weight, content uniformity, hardness, dissolution) are met, or rework the batch properly by remelting and re‑casting under controlled conditions.

Why:
- Using a heat gun risks uneven, excessive localized heating (melting, scorching, or degrading the base or active), and is hard to control for reproducible appearance.
- Pouring more liquid into finished troches changes mass and could alter dose uniformity and drying times.
- Leaving them is acceptable only if they meet all quality/specification parameters and the appearance does not violate labeling/packaging requirements.

Practical, safer options (high level):
- If you need to fix appearance, remelt the batch uniformly (use a controlled water bath or a calibrated heating device rather than a hot air gun), degas if needed, then re‑pour into clean molds. This yields the most consistent, “pharmaceutically elegant” result.
- For minor smoothing, a gently warmed (not scorching) flat metal spatula or a warmed mold top can be used to level the surface — but do this only if the active is heat-stable and you can avoid contamination and dose change.
- Always check weights/content uniformity and stability after any rework. Document the deviation and corrective action per your SOPs and regulatory requirements. If in doubt, discard and remake.

So: prefer controlled remelt/re‑pour for best appearance and consistency; otherwise leave them if specifications are met.