Partial Hospitalization Program (PHP) for Substance Use: How It Works

What a Partial Hospitalization Program Is

In the ASAM framework, partial hospitalization is Level 2.5. An ASAM-based service description from 2020 defines it as a structured program, also called day treatment, for patients whose medical, psychiatric or cognitive needs call for daily monitoring or management but can still be handled in a structured outpatient setting. The minimum is "20 or more hours of clinically intensive programming per week," set through the treatment plan.

Montana's Medicaid provider manual uses the same 20-hour minimum, describes PHP as aimed at helping members function better at home, in school or in the community, and requires direct access to psychiatric, medical and laboratory services on site. Federal TIP 47 guidance adds a marker from the other side of the line: it treats a program with daily 6-hour sessions as partial hospitalization rather than intensive outpatient care, and says the boundaries between levels are not sharp. Two cautions apply. The hour counts come from a 2020 document and one state's manual, and ASAM's criteria are now in their Fourth Edition, released in 2023, so programs and payers may define the level a little differently. The numbers are a reference point, not a rule every program follows.

What a Typical PHP Week Looks Like

No single week fits every program. The ASAM-based description lists the services a program at this level provides:

• Individual, group, couples and family therapy
• Medication management and educational groups
• Occupational, recreational, art and movement therapies
• Motivational approaches preferred over confrontation
• Individualized care with measurable goals, reviewed across the six ASAM dimensions

The same description says programs are run by an interdisciplinary team that can include addiction counselors, psychologists, social workers and addiction-credentialed physicians, with medical and psychiatric consultation available within 8 hours by phone and 48 hours in person, and emergency phone support around the clock when the program isn't in session. The table below shows one way 20 hours might be arranged. It illustrates the minimum and is not a schedule from any real program; some programs run fewer days with longer hours.

How Long a Partial Hospitalization Program Usually Lasts

There's no universal length. Neither the ASAM-based description nor the Montana manual sets a fixed length of stay. The ASAM-based description says intensity and frequency are adjusted to the patient's progress, with the plan reviewed at set intervals or as needed, and the Montana manual ties continued care to meeting the clinical criteria for the level.

One research example gives a feel for the scale. In a 2007 study of a managed care plan, a planned day hospital stay ideally included 2 to 3 weeks of day hospital, followed by 5 to 6 weeks of outpatient treatment and then aftercare. That is one setting from nearly twenty years ago, and programs today may run shorter or longer. So the honest answer is a range set by assessment, progress and program design, and a step down usually leads to a less intensive level such as intensive outpatient care and, later, aftercare.

PHP Compared With Intensive Outpatient, Standard Outpatient and Residential Care

The levels sit on a continuum. PHP is more intensive than intensive outpatient care and less intensive than a residential stay, where a person lives at the facility. The ASAM-based description names one real difference from IOP: this level has direct access to psychiatric, medical and laboratory services, which makes it better able to handle needs that warrant daily monitoring.

The table is a simplification, and as TIP 47 notes, the lines between levels are blurry. The levels of care guide lays out the full ladder, and the directory lists residential rehab centers and inpatient rehab centers for settings with overnight stays.

Who PHP Tends to Suit

A clinician usually decides this through an assessment, and this guide can't say what any person needs. The ASAM-based description says the level fits needs that warrant daily monitoring or management but can be addressed in a structured outpatient setting. The Montana manual says members must meet the state's substance use disorder criteria and ASAM's criteria for the level, and must be willing and able to take an active part.

TIP 47 puts the broader principle simply: the key question isn't whether inpatient or outpatient care is better, but which level fits a person at a given time. Because assessments repeat, a person can move up or down a level as needs change. If someone is in immediate danger, call 911. For suicidal thoughts or emotional crisis, call or text 988.

Therapies and Medications Commonly Part of PHP

At this level, therapy is the center of the day. The ASAM-based description lists individual, group, couples and family therapy, educational groups and a range of adjunct therapies, with medication management as a listed service. The Montana manual's bundle includes individual, group and family therapy and educational groups, with psychiatric, medical and laboratory services on site.

Medication is part of some programs and not others. In our directory, 77.0% of federally listed PHP programs also list medication-assisted treatment. This guide doesn't recommend any medication or dose; those are decisions between a person and a prescriber. Co-occurring mental health conditions are a common reason this level is considered, because of its psychiatric access, and 89.5% of listed PHP programs report treating them. The dual diagnosis guide covers integrated care.

What the Research Says About PHP Outcomes

The evidence for PHP is thinner than for IOP. Much of the research is older, comes from single settings, and compares PHP with residential care rather than with other outpatient levels. The clearest example is a 2007 study of 696 clients in a managed care plan, published in the Journal of Consulting and Clinical Psychology. Some clients were randomly assigned to day hospital or community residential treatment; others chose day hospital or were directed to residential care. More than half of followed clients reported no use in the past 30 days at 6 and 12 months, with no significant difference between day hospital and residential care, and days in the index program and 12-step attendance were both linked to abstinence. The authors listed several limits:

• Placement wasn't fully matched. Randomized clients met only five of the six ASAM criteria for residential placement.
• Substance use was self-reported and not confirmed with biological or outside measures.
• Follow-up dropped to 59% in one group at 12 months, and the authors said some results may be somewhat inflated.
• The residential programs followed a social model, so findings may not apply to other residential models.

What isn't known well: how PHP compares with intensive outpatient care today, which program features matter most, and how telehealth versions perform. PHP is an established level of care, and the available evidence doesn't promise any result for a given person.

How Insurance Typically Treats PHP

This section is general and doesn't describe any one insurer or plan. Some payers and state programs treat PHP as its own level of care and review it against clinical criteria, and some state definitions require that a person meet ASAM's criteria for the level. The federal Mental Health Parity and Addiction Equity Act, as described by the Department of Labor, requires plans that cover substance use disorder benefits to do so in a way comparable to medical and surgical benefits. Parity does not require coverage of any specific level or length of care.

Coverage, network status, authorization requirements, deductibles and copays vary by plan, and reported payer participation does not guarantee coverage for a specific plan. Plan-specific details are confirmed directly with the insurer and the program.

What Federal Listings Show About PHP Access

PHP takes up most of the day, most days of the week, so location and format matter a great deal. Our directory, built from federal facility records, lists 1,815 programs that report offering partial hospitalization, 15.6% of the 11,650 programs we list. That is roughly a third as many as offer intensive outpatient care, so choices are narrower.

Among those PHP programs, 81.7% also list telehealth, which can make daily attendance more realistic. 92.8% also offer IOP and 26.9% offer residential care, which matters for anyone who may step down or up without changing programs. Roughly a quarter don't list medication-assisted treatment, so it is worth asking each program whether medication is part of the plan. A state with few listed programs usually means longer travel or fewer choices. These are federally listed programs as reported, and listings don't evaluate quality or fit.