Pharmacology for Physical & Occupational Therapists: The Medications That Are Quietly Changing Your Treatment Outcomes

Most physical therapists enter the clinic thinking about movement, tissue, load, and motor control. Medications are someone else's department. And for the most part, that boundary is appropriate — PTs aren't prescribers, and nobody's asking us to be.

The problem is that the medications your patients are taking are already inside your treatment room, whether you're accounting for them or not. A patient on a GLP-1 weight loss drug is losing muscle mass at the same time you're trying to build it. A patient on gabapentin for neuropathic pain is walking into balance and coordination work with compromised neuromuscular control and fall risk baked into their baseline. A patient who finished a course of Cipro three weeks ago may have connective tissue that is structurally compromised in ways that won't show up on any imaging until a tendon fails under load. None of these are prescribing decisions. All of them are clinical reasoning decisions — and the PT who knows what to look for makes better ones.

Here's a breakdown of the drug classes most relevant to PT practice and what they actually mean for how you treat.

GLP-1 Agonists: The Weight Loss Drugs Creating a PT Caseload

Semaglutide (Wegovy / Ozempic) and tirzepatide (Zepbound) are now among the most prescribed medications in the country. They work by mimicking metabolic hormones that slow gastric emptying and suppress appetite, producing dramatic weight loss in many patients — sometimes 15–25% of total body weight over the course of treatment. For patients with obesity-related joint loading, cardiovascular risk, and metabolic disease, the clinical benefits are real and meaningful.

For physical therapists, so is the risk profile.

Rapid, significant weight loss achieved primarily through caloric restriction — which is how GLP-1 medications work — produces what's known as compositional weight loss, not just fat loss. Studies consistently show that without deliberate resistance training, patients on GLP-1 medications lose lean muscle mass alongside adipose tissue. In older adults, this is a direct path to sarcopenia, reduced bone density, decreased functional reserve, and elevated fall risk. The patients who need the most aggressive and targeted PT resistance programming are often the ones most likely to attribute their progress exclusively to the medication and deprioritize exercise.

The PT role here is not supplementary — it's protective. Targeted progressive resistance training is the primary clinical intervention that prevents muscle and bone loss during GLP-1 therapy. These patients need loading that is specific, progressive, and monitored, not generic "exercise." If you're treating a patient on a GLP-1 and your plan doesn't include a deliberate resistance component with attention to lean mass preservation, that's a gap in the clinical picture that matters for their long-term functional health.

GLP-1s can have a big impact on weight but also on lean mass too!

Gabapentin, Statins, and the Medications That Masquerade as Your Diagnosis

Two drug classes — gabapentinoids and statins — are responsible for a small amount of the clinical presentations that PTs misattribute to deconditioning, aging, or can effect a patient's underlying diagnosis.

Gabapentin is prescribed broadly for neuropathic pain, sciatica, and fibromyalgia, and it's genuinely effective at down-regulating overactive nerve signaling. The side effect profile is where the PT-specific concerns live: dizziness, impaired coordination, cognitive slowing and word-finding difficulty, and elevated fall risk are common, particularly at higher doses or when patients are also taking other CNS-active medications. A patient on gabapentin who appears "slow," who struggles with dual-task activities, or whose balance is worse than their diagnosis would predict — that's not necessarily them; that may be the medication. Adjusting your expectations, your session pacing, and your fall risk assessment accordingly is basic clinical competency once you know to look for it.

What's less well-known is that compounding pharmacies can formulate gabapentin as a transdermal cream, often in combination with an anti-inflammatory like diclofenac, applied directly to the pain site. This delivers localized analgesia without the CNS side effects that make systemic gabapentin so disruptive to coordination and cognition. If you have a patient who is struggling on oral gabapentin but has a localized pain presentation, this is worth a conversation with their prescriber — not as a prescription recommendation from you, but as clinical information that's relevant to the overall care plan. Compounding pharmacists can also design step-down titration schedules for patients working toward discontinuation, which is relevant for PTs treating patients whose long-term goal is medication reduction alongside functional improvement.

Statins are the cholesterol-lowering medications taken by a proportion of patients over 50, and statin-induced myopathy is one of the most underrecognized contributors to unexplained muscle presentations in outpatient PT. The mechanism involves impairment of mitochondrial function in muscle cells, leading to widespread aching, cramping, and systemic weakness — not soreness from training, but diffuse muscular discomfort that doesn't track with exercise load or activity level.

The screening question is straightforward: when a patient reports aching or weakness in muscle groups that are not the target of their current rehab program, and especially when that discomfort is bilateral or generalized, statins are on the differential. Elevated creatine kinase (CK) on lab work is a confirmatory finding. For high-intensity athletes and physically active patients, statin myopathy can significantly limit training adaptation and recovery — and for those patients, communicating your clinical observations to the prescriber (framed as "the patient's muscle response to loading is inconsistent with expected adaptation; CK may be worth checking") is appropriate and often welcomed. Switching drug classes within the statin family, or adjusting dose or timing, is sometimes enough to resolve the presentation.

Statins and Gabapentin can have potential impacts on rehab plans - be sure to check in with the patient to see how they are feeling since onset of medication use.

Fluoroquinolones: The Antibiotic That Can Rupture a Tendon

This is the most urgent pharmacology flag for PT practice, and it remains underappreciated.

Fluoroquinolone antibiotics — ciprofloxacin (Cipro) and levofloxacin are the most common — carry an FDA black box warning for tendon rupture risk. The mechanism involves impairment of collagen synthesis and degradation of existing collagen in connective tissue, which can structurally weaken tendons — most famously the Achilles, but any tendon under load — to the point of acute rupture under stress that would otherwise be well within normal functional range.

The clinical complication is the time window. This risk does not end when the antibiotic course ends. Vulnerability can persist for four to eight weeks after the last dose, which means a patient who took a course of Cipro for a urinary tract infection last month and is now presenting for PT for an unrelated musculoskeletal complaint has connective tissue that is not at its structural baseline — even if they feel fine and their tendon is asymptomatic. If that patient is progressing through a plyometric program, a return-to-sport protocol, or any loading that places significant tensile demand on major tendons, that history matters.

The screening question is simple: "Have you been on an antibiotic in the last two months? Do you know what kind?" Patients rarely connect antibiotics to musculoskeletal risk without being asked. If a patient on or recently off a fluoroquinolone develops acute tendon pain during a session, activity should be paused or loading diminished.. And if you're progressing a patient with a recent fluoroquinolone history, loading progression should be appropriately conservative regardless of their functional presentation.

OTC Medications: The Mechanism Difference That Changes Patient Education

Ibuprofen and acetaminophen are used interchangeably by most patients, and treating them as equivalent is a common source of mismatched expectations and suboptimal pain management decisions.

Ibuprofen is a COX inhibitor that works at the site of tissue inflammation — it reduces local prostaglandin production and genuinely blunts the inflammatory process. For acute musculoskeletal injury where inflammation is the primary driver of pain, ibuprofen addresses the mechanism. It also carries the implications discussed earlier regarding healing cascades — COX inhibition affects prostaglandin-driven tissue repair, which matters for loading timelines in healing structures.

Acetaminophen works centrally, in the brain, altering pain perception without affecting the inflammatory process. It doesn't treat inflammation; it changes how the nervous system registers the signal. For patients whose pain is centrally amplified, centrally maintained, or independent of active tissue inflammation, acetaminophen may actually be more appropriate — and for patients who cannot take NSAIDs due to kidney disease, anticoagulant use, or GI sensitivity, it's often the only OTC option.

Educating patients on this difference can be clinically useful, and often resolves the "I took ibuprofen and it didn't help" conversation in a way that actually leads somewhere productive. Clearly if there are more concerns it's always advisable to have them follow up with their physician.

The Integrative View

What ties these drug classes together is a broader clinical principle: the body that shows up to physical therapy is a complete biological system, not just the joint or tissue you're treating. Hormonal status, gut health, systemic inflammation, and medication load all shape the environment in which rehabilitation happens. A PT who evaluates movement but doesn't ask about the systemic context is working with incomplete information.

This is the argument for pharmacology awareness as a core PT competency — not as scope expansion, but as clinical depth. Knowing what your patients are taking, knowing what those medications do, and knowing when the medication picture is relevant to the treatment plan is what separates good clinical reasoning from good technique.

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Neema Yazdanpanah PharmD of Ion Integrative Pharmacy joined Jay and Randal live to break down all of this — and more — including how a pharmacist's systemic view of patient health intersects with what PTs see in the clinic every day. Watch the You Tube Video here (Don’t forget to follow us on You Tube for more amazing content!)