PST is generally considered safe and effective, especially for depression, but like any therapeutic approach, it’s not a one-size-fits-all solution.

1. Not ideal for severe mental illness

PST may not be useful on its own for:

• • Severe major depressive disorder.
  • Psychosis.
  • Bipolar disorder.
  • Acute suicidal ideation.

These conditions often require more intensive or comprehensive care, like medication, longer-term therapy, and crisis intervention.

Why? PST focuses on rational problem-solving. But in states of severe cognitive impairment or emotional dysregulation, clients might struggle to engage with the structured steps.

2. May overemphasize “fixing” problems

It teaches people to take practical action, but not all emotional pain can be “solved”.

Some issues (grief, trauma, existential crises) require:

• • Emotional processing.
  • Acceptance-based work.
  • Greater exploration of beliefs or patterns.

If a therapist pushes too hard for solutions without validating the emotional experience, clients may feel invalidated or rushed.

3. Cognitive demands can be too high for some
   
   

PST requires:

• • Goal setting.
  • Planning.
  • Decision-making.
  • Evaluating outcomes.

This can be too much for clients with executive dysfunction, cognitive decline, or brain fog (due to depression, ADHD, long COVID, or neurodegenerative disorders).

A study by Alexopoulos et al. noted that while PST can help elderly adults with cognitive decline, it must be adapted and simplified.

4. Risk of oversimplifying complex problems

Some life challenges aren’t easily broken down into “steps,” like:

• • Chronic relational patterns.
  • Identity issues.
  • Systemic oppression or poverty.

PST’s controlled approach can feel too narrow or surface-level for clients dealing with complex trauma or multilayered life issues.

5. Requires motivation and follow-through
   
   

Clients are expected to:

• • Practice skills between sessions.
  • Try solutions in real life.
  • Reflect on what works or doesn’t.

This assumes a baseline level of motivation, energy, and executive functioning, which may be hard for people with severe depression, burnout, or fatigue.

It may also reinforce feelings of helplessness or guilt if a client doesn’t complete homework or “fails” at solving problems.

6. Not aimed at emotional insight or relational patterns

Unlike psychodynamic or interpersonal therapies, PST doesn’t dive into:

• • Attachment issues.
  • Past trauma.
  • Relationship dynamics.
  • Core beliefs or unconscious drives.

This means that PST can feel too “mechanical” or “shallow” for clients wanting emotional depth.

7. Therapist skill matters
   
   

Poor delivery of PST can lead to:

• • Rigid or formulaic sessions.
  • Lack of empathy or emotional attunement.
  • Ignoring context in favor of “fixing”.

A well-trained therapist will still bring empathy, flexibility, and clinical judgment instead of just sticking to the protocol blindly.

PST works best when matched to the client’s needs, adapted when necessary, and delivered with flexibility and empathy.