Mapping the Gaps: What We Know and Don’t Know About Cannabis for Symptom Management in HIV and Cancer

A scoping review of 51 observational studies finds mostly cross-sectional evidence, no data on patients with both conditions, and critical gaps in dosing and safety information that limit clinical translation.

Why This Matters

Medical cannabis is now approved in 38 U.S. states, and cannabis nursing has been formally recognized as an American Nurses Association specialty practice. People living with HIV, cancer, or both frequently report using cannabis for symptom relief, and clinicians are increasingly asked to guide that use. Yet the assumption that a large body of real-world evidence supports these conversations deserves scrutiny. This scoping review arrives at a critical moment, mapping the actual state of the observational literature and revealing how thin the foundation is beneath a rapidly expanding clinical practice area.

Clinical Summary

Symptom burden in HIV and cancer remains substantial despite advances in antiretroviral therapy and oncologic treatment. Pain, fatigue, anxiety, depression, nausea, and sleep disturbance are common across both populations, and cannabis is one of the most frequently self-reported complementary therapies. A 2025 scoping review by Dominguez and colleagues, published in the Journal of Clinical Nursing, systematically mapped observational quantitative studies published between 2017 and November 2022 to characterize what is known about real-world cannabis use for symptom management in these populations. The review followed the PRISMA-ScR framework and searched PubMed, PsycInfo, CINAHL, and Embase, ultimately including 51 studies from an initial screen of 1,738 abstracts. The mechanistic rationale centers on the endocannabinoid system’s role in modulating pain signaling, inflammation, mood, appetite, and sleep, though the included studies were not designed to test mechanistic hypotheses.

Among the 51 included studies, 37 were cross-sectional, 11 were cohort designs, and 3 were case-control studies. The literature was predominantly U.S.-based and more heavily weighted toward cancer populations than HIV populations. Some HIV studies reported positive associations between cannabis use and antiretroviral therapy adherence and undetectable viral load, while others found associations with improved sleep duration but not sleep efficiency. Critically, no studies examined cannabis use among people living with both HIV and cancer, a population of growing clinical importance as life expectancy with HIV increases and cancer incidence in this group rises. Dosing, delivery mode, and standardized safety data were largely absent. The authors conclude that prospective, longitudinal studies with standardized outcome measures and defined dosing parameters are needed before clinical recommendations can be responsibly formulated.

Dr. Caplan’s Take

This review does something genuinely valuable: it takes a step back from the enthusiasm around medical cannabis and asks what the real-world evidence actually looks like. The answer is sobering. Thirty-seven of 51 studies are cross-sectional snapshots, most lack dosing information, and the comorbid HIV-cancer population has been entirely overlooked. When patients in my practice ask whether cannabis might help manage their symptoms, I owe them an honest accounting of how little structured evidence exists rather than a reassuring gesture toward a body of literature that is far more fragmented than it appears.

In practice, I do not dismiss cannabis as a potential adjunct for symptom management, but I frame conversations around the limits of what we know. I emphasize that perceived benefit in surveys is not the same as demonstrated efficacy, that drug interactions with antiretrovirals and chemotherapeutic agents remain poorly characterized, and that self-directed dosing without clinical oversight carries real risk. For patients already using cannabis, I document their use, monitor for interactions, and work to keep the conversation clinical rather than ideological.

Clinical Perspective

This scoping review sits at the earliest stage of the research arc: landscape mapping. It confirms that patients with HIV and cancer are using cannabis for symptom management, often without clinical guidance, but it does not and cannot confirm that cannabis is effective or safe for these purposes. The dominance of cross-sectional designs means that associations between cannabis use and symptom outcomes could reflect reverse causation or confounding just as easily as therapeutic benefit. The complete absence of data on the comorbid HIV-cancer population is particularly notable for clinicians managing these patients, as this group faces compounded symptom burden, polypharmacy, and distinct pharmacokinetic considerations. The evidence does not currently support condition-specific cannabis recommendations for either population, let alone the comorbid group.

Clinicians should be particularly attentive to potential cannabis-drug interactions in these populations. Cannabinoids are metabolized through cytochrome P450 pathways (notably CYP3A4 and CYP2C9), which overlap with the metabolic pathways of many antiretrovirals, including protease inhibitors and non-nucleoside reverse transcriptase inhibitors, as well as multiple chemotherapeutic agents. Altered drug levels could affect virologic suppression or treatment toxicity. One concrete, actionable step clinicians can take now is to proactively ask about cannabis use during medication reconciliation in every HIV and oncology encounter, document the mode and frequency of use, and screen for potential metabolic interactions with current regimens.

Study at a Glance

Study Type

Scoping review (PRISMA-ScR)

Population

Adults with HIV or cancer; no studies identified in comorbid HIV and cancer

Intervention

Self-reported cannabis use (various forms, largely unspecified dosing)

Comparator

Non-users or varying levels of use within observational designs

Primary Outcomes

Symptom management patterns, perceived effectiveness, dosing and delivery characterization, evidence gaps

Sample Size

51 included studies from 1,738 screened abstracts

Databases Searched

PubMed, PsycInfo, CINAHL, Embase

Search Window

2017 to November 2022

Journal

Journal of Clinical Nursing

Year

2025

Funding Source

NIH/NIAAA

What Kind of Evidence Is This

This is a scoping review conducted according to the PRISMA-ScR checklist, designed to map the breadth and nature of observational research on cannabis for symptom management in HIV and cancer. Scoping reviews sit below systematic reviews and meta-analyses in the evidence hierarchy because they do not assess risk of bias in included studies or grade the quality of evidence. The most important inference constraint is that findings describe the landscape of existing research rather than synthesizing its conclusions, meaning this review cannot support claims about cannabis efficacy or safety.

How This Fits With the Broader Literature

This review builds on an earlier 2017 review that served as its search baseline and extends the mapping through November 2022. Its findings are consistent with broader critiques of the medical cannabis evidence base, including a 2017 National Academies of Sciences report that identified substantial evidence for cannabinoids in chronic pain, chemotherapy-induced nausea, and spasticity but noted critical gaps in standardized dosing, long-term safety, and vulnerable populations. The current scoping review reinforces the National Academies’ concern by documenting that even the observational literature lacks the dosing, safety, and delivery mode data needed for clinical translation. The identification of a complete evidence void for the comorbid HIV-cancer population is a novel contribution and may help direct future research funding and study design toward this underserved group.

Common Misreadings

The most likely overinterpretation is to treat the finding that cannabis use is “associated with” improved symptoms or treatment adherence in some observational studies as evidence that cannabis is effective for these outcomes. Cross-sectional associations cannot establish causation. People who use cannabis and report fewer symptoms may differ from non-users in unmeasured ways, and those who experience benefit may be more likely to continue use and therefore appear in prevalence studies. Similarly, the fact that 51 studies were included should not be read as indicating a robust evidence base; the volume of studies does not compensate for the uniformly low inferential power of the designs involved.

Bottom Line

This scoping review clarifies that the observational evidence on cannabis for symptom management in HIV and cancer is extensive in volume but limited in methodological rigor, with cross-sectional designs dominating and critical data on dosing, safety, and delivery largely absent. The complete absence of research on the comorbid HIV-cancer population is a significant gap. This review does not support clinical cannabis recommendations for these populations but provides a useful map for where research investment is most urgently needed.

References

1. Dominguez D, et al. Cannabis use for symptom management in people living with HIV or cancer: A scoping review of observational quantitative studies. Journal of Clinical Nursing. 2025. (Funded by NIH/NIAAA.)
2. National Academies of Sciences, Engineering, and Medicine. The health effects of cannabis and cannabinoids: The current state of evidence and recommendations for research. Washington, DC: The National Academies Press; 2017. DOI: 10.17226/24625.