Performance enhancement drugs: what they are, what they do, and what they cost

Performance enhancement drugs sit in an uncomfortable space between legitimate medicine and risky self-experimentation. In clinics, I see them as real therapies with clear indications—treatments that restore function, protect organs, or replace missing hormones. Outside clinics, I see the same molecules repackaged as shortcuts: “more muscle,” “more stamina,” “more focus,” “more confidence.” The human body is messy, though. Push one lever, and three other systems move.

To keep this article medically grounded, I’m going to use “performance enhancement drugs” as an umbrella term for several pharmacologic classes that people use to enhance athletic, cognitive, or sexual performance. That includes anabolic-androgenic steroids (generic examples: testosterone, nandrolone, stanozolol), erythropoiesis-stimulating agents (generic: epoetin alfa, darbepoetin alfa), central nervous system stimulants (generic: amphetamine salts, methylphenidate, modafinil), beta-2 agonists (generic: salbutamol/albuterol), and PDE5 inhibitors used for erectile function (generic: sildenafil, tadalafil; brand examples: Viagra, Cialis). You’ll also hear about growth hormone, insulin, thyroid hormone, and a long tail of “research chemicals.” Some are prescription medicines. Some are not approved for human use at all.

Why does this topic matter? Because the same drug can be a lifesaver in one context and a slow-motion health disaster in another. I’ve had patients who needed testosterone replacement for true hypogonadism and felt like themselves again. I’ve also met young athletes who bought “testosterone” online that turned out to be a mystery oil. One story is medicine. The other is roulette.

This piece covers what these drugs are used for in real medical practice, what is myth versus physiology, and where the risks actually live—blood pressure, clotting, heart rhythm, liver injury, infection, psychiatric effects, fertility, and more. We’ll also talk about the social side: doping rules, counterfeit markets, and why “everyone’s doing it” is almost always an illusion.

If you want related background, you can also read our overviews on medication safety and interactions and hormone health basics. They pair well with this topic.

Medical applications

Let’s be blunt: performance enhancement drugs are not one drug. They’re a category of medications and hormones with different targets, different benefits, and wildly different risk profiles. In medicine, the goal is usually restoration—bringing a deficient system back toward normal. In non-medical use, the goal is often supra-physiologic—pushing beyond normal. That difference drives most of the harm I see.

Primary indication: treating diagnosable disease (not “optimization”)

In clinical practice, the “primary use” of drugs that later get labeled as performance enhancers is straightforward: treat a defined condition with evidence-based benefit. A few common examples:

• Testosterone (therapeutic class: androgen/anabolic steroid hormone) is prescribed for male hypogonadism with consistent symptoms and confirmed low levels on appropriate testing. The medical goal is improved sexual function, bone health, anemia related to deficiency, and overall wellbeing—not bodybuilding.
• Epoetin alfa / darbepoetin alfa (therapeutic class: erythropoiesis-stimulating agents) are used for anemia in settings like chronic kidney disease or chemotherapy-associated anemia. The goal is to reduce transfusion needs and improve anemia-related symptoms under careful monitoring.
• Methylphenidate and amphetamine formulations (therapeutic class: CNS stimulants) are used for ADHD and, in some cases, narcolepsy. When properly prescribed and monitored, they improve attention and executive function in people with a clear diagnosis.
• Modafinil/armodafinil (therapeutic class: wakefulness-promoting agents) are used for narcolepsy and certain sleep-wake disorders. In clinic, the aim is safety and daytime function—think driving, working, staying awake in meetings—rather than “biohacking.”
• Sildenafil and tadalafil (therapeutic class: PDE5 inhibitors) are used for erectile dysfunction and also for pulmonary arterial hypertension (under different dosing and monitoring frameworks). Their value is quality of life and, for pulmonary hypertension, hemodynamic benefit.
• Albuterol/salbutamol (therapeutic class: beta-2 agonist bronchodilator) is used for asthma and bronchospasm. The point is breathing, not speed.

Patients often ask me a question that sounds simple: “If it helps sick people, why is it dangerous for healthy people?” Because the dose-response curve and the baseline physiology differ. Correcting deficiency is not the same as forcing excess. A body that’s already in range doesn’t “store” the benefit neatly; it pays for it elsewhere.

Another reality: these drugs are rarely cures for the underlying cause. Testosterone doesn’t fix a pituitary tumor. Stimulants don’t erase sleep deprivation, depression, or chaotic work schedules. PDE5 inhibitors don’t resolve uncontrolled diabetes or severe vascular disease. They can be clinically valuable tools, but they don’t rewrite biology.

Approved secondary uses (where the label actually supports it)

Several drugs associated with performance have legitimate secondary indications that people outside medicine don’t realize exist.

PDE5 inhibitors: Sildenafil and tadalafil are widely known for erectile dysfunction, but they also have an established role in pulmonary arterial hypertension. That’s not “better cardio.” It’s targeted vasodilation in the pulmonary circulation to improve symptoms and exercise tolerance in a serious cardiopulmonary disease under specialist care.

Stimulants: Certain stimulant medications are used for narcolepsy and related disorders. In those patients, the benefit is not a “competitive edge.” It’s the ability to function safely. I’ve had patients describe it as the difference between living in a fog and being able to keep a job. That’s a medical outcome, not a lifestyle flex.

Beta-2 agonists: Inhaled bronchodilators are essential for asthma management. When someone without asthma uses them to chase a “breathing boost,” they’re borrowing from the heart—tachycardia, tremor, anxiety—without any real lung disease to treat.

Testosterone: Beyond hypogonadism, testosterone can be used in certain gender-affirming care contexts, with structured monitoring and informed consent. That is a different clinical framework than athletic enhancement, and it deserves to be discussed with the seriousness it warrants.

Off-label uses (clinicians sometimes consider, with caution)

Off-label prescribing is common in medicine, but it’s not a free-for-all. It means the clinician believes the evidence and physiology support a use that isn’t on the official label, and that the risk-benefit balance makes sense for that patient.

Examples that come up in real practice include:

• Testosterone for carefully selected cases of delayed puberty under specialist guidance, or for specific endocrine disorders. This is not a gym plan; it’s pediatric/endocrine medicine with long-term implications.
• Modafinil for excessive sleepiness in contexts outside the strictest labeled indications, when sleep medicine evaluation supports it. When I see it used well, it’s paired with a serious look at sleep apnea, circadian rhythm, and medication side effects.
• PDE5 inhibitors explored for certain lower urinary tract symptoms or other vascular-related complaints, depending on guidelines and patient factors.

Off-label use still requires monitoring, a clear rationale, and a plan for side effects. What it does not require is a forum thread and a credit card.

Experimental / emerging uses (interesting, but not settled)

Research on performance-adjacent medications is active, and the internet tends to inflate early findings into certainty. A few areas that get attention:

• Selective androgen receptor modulators (SARMs) are often marketed as “safer steroids.” They are not approved for bodybuilding, and safety signals have raised concern. The evidence base for long-term outcomes is limited, and product purity is a recurring problem.
• Peptides and growth hormone secretagogues circulate widely online. The clinical evidence for “recomposition” or “anti-aging” claims is not robust, and endocrine disruption is a real concern.
• Novel stimulants/nootropics appear faster than medical literature can evaluate them. When a compound is sold as “research only,” that’s not a wink; it’s a warning label.

I often tell people: medicine moves slowly on purpose. That pace is frustrating until you’re the one dealing with an arrhythmia or liver injury from an “innovative stack.”

Risks and side effects

Risk is not evenly distributed across this category. A supervised prescription for a clear diagnosis is one scenario. Unsupervised polypharmacy is another. The harms I see most often come from three patterns: excess dosing, combining drugs, and unknown product quality.

Common side effects

Common does not mean trivial. It means “frequent enough that clinicians expect it and counsel about it.”

• Anabolic-androgenic steroids/testosterone: acne, oily skin, hair loss in genetically susceptible people, mood changes, irritability, fluid retention, changes in libido, and testicular shrinkage with suppressed endogenous production. Patients tell me the skin changes alone can be socially brutal.
• Stimulants: decreased appetite, insomnia, dry mouth, increased heart rate, jitteriness, anxiety, and headaches. A lot of people interpret the early “wired” feeling as productivity; it can slide into agitation quickly.
• PDE5 inhibitors (sildenafil/tadalafil): headache, flushing, nasal congestion, indigestion, and sometimes back or muscle aches (more often reported with tadalafil). Visual color tinge can occur with sildenafil due to cross-reactivity with retinal enzymes.
• Erythropoiesis-stimulating agents: injection-site reactions and rises in blood pressure are common clinical issues, which is why monitoring is routine.
• Beta-2 agonists: tremor, palpitations, anxiety, and low potassium in higher exposures. People are often surprised how “full body” a lung medicine can feel.

If side effects show up, the safest next step is a clinician conversation, not a workaround. I’ve watched too many people chase one drug’s side effect with another drug, then lose track of what started the cascade.

Serious adverse effects

Serious complications are less common, but they’re the reason sports medicine and cardiology clinics keep seeing the same stories.

• Cardiovascular events: elevated blood pressure, arrhythmias, heart attack, and stroke risk can rise depending on the drug, dose, and individual risk factors. Stimulants and anabolic steroids are frequent culprits in different ways.
• Blood clots and “thick blood” physiology: testosterone can raise hematocrit in some users; erythropoiesis-stimulating agents directly increase red blood cell production. More red cells can mean more viscosity, which is not a badge of fitness.
• Liver injury: oral anabolic steroids (especially 17-alpha-alkylated compounds) are associated with hepatotoxicity. I’ve seen lab panels that looked like a wildfire—then the person admits the “oral cycle” three visits later.
• Psychiatric effects: anxiety, panic, irritability, aggression, and mood instability can occur with stimulants and androgens. Sleep deprivation amplifies all of it. That combination is a classic recipe for bad decisions.
• Fertility and endocrine disruption: suppressing the hypothalamic-pituitary-gonadal axis can reduce sperm production and impair fertility. Recovery is unpredictable.
• Priapism and sudden hearing/vision symptoms: rare but urgent issues reported with PDE5 inhibitors. Any prolonged, painful erection or sudden sensory loss warrants emergency evaluation.
• Infection and tissue injury: non-sterile injections and shared equipment can transmit infections and cause abscesses. This is not theoretical; it’s a weekly reality in many urgent care settings.

Red-flag symptoms that deserve urgent medical attention include chest pain, fainting, severe shortness of breath, one-sided weakness, severe headache unlike prior headaches, confusion, or sudden vision/hearing changes. That’s not drama. That’s triage.

Contraindications and interactions

Contraindications vary by drug class, but a few themes repeat.

• PDE5 inhibitors: dangerous interaction with nitrates (used for angina) and caution with certain alpha-blockers and blood pressure medications due to hypotension risk. Mixing with “poppers” (amyl nitrite) is a well-known emergency-room storyline.
• Stimulants: caution or avoidance in uncontrolled hypertension, certain arrhythmias, and in people with significant anxiety or certain psychiatric histories. Interactions with other stimulants, decongestants, and some antidepressants can raise risk of tachycardia, hypertension, or serotonin toxicity depending on the combination.
• Anabolic-androgenic steroids/testosterone: caution in prostate cancer, severe untreated sleep apnea, high hematocrit, and uncontrolled heart failure; interactions with anticoagulants and effects on lipids and glucose can complicate other chronic disease management.
• Erythropoiesis-stimulating agents: careful use in people with uncontrolled hypertension and those at higher thrombotic risk, with monitoring targets set by clinical guidelines.

Alcohol deserves its own mention: it doesn’t “mix” cleanly with performance drugs. It worsens sleep, increases injury risk, and can magnify blood pressure swings and risky decision-making. Patients laugh when I say this, then admit they only take the stimulant because they drank the night before. That loop is common.

Beyond medicine: misuse, myths, and public misconceptions

Misuse is not restricted to elite sport. It’s in gyms, offices, campuses, and group chats. The pattern I hear is oddly consistent: someone starts with a legitimate goal—fat loss, confidence, productivity—then gets pulled into escalating complexity. The “stack” grows. The monitoring doesn’t.

Recreational or non-medical use

Non-medical use tends to cluster into a few buckets:

• Muscle and physique: anabolic steroids, SARMs, growth hormone, insulin, thyroid hormone. The promise is rapid recomposition. The bill often arrives later as dyslipidemia, hypertension, endocrine suppression, or injury from training beyond connective tissue capacity.
• Endurance: erythropoiesis-stimulating agents, stimulants, and sometimes thyroid hormone. The physiology is straightforward—more oxygen-carrying capacity or more drive—but the clotting and cardiac risks are not subtle.
• Focus and “hustle”: prescription stimulants and modafinil obtained without appropriate evaluation. People describe it as turning the volume down on distraction. Then sleep collapses, anxiety spikes, and the baseline problem—workload, depression, untreated ADHD, or poor sleep—remains.
• Sexual performance: PDE5 inhibitors used as confidence aids even without erectile dysfunction. Patients tell me it’s “just in case.” That mindset can backfire by increasing performance anxiety and encouraging unsafe combinations.

Here’s a question I ask in clinic: “What are you trying to fix?” The answer is rarely “my hemoglobin is low from kidney disease.” It’s usually identity, pressure, or fear of falling behind. Biology doesn’t care about any of that.

Unsafe combinations

Combining drugs is where unpredictability explodes. A few combinations that repeatedly cause harm:

• Stimulants + other stimulants (energy drinks, pre-workouts, decongestants): additive strain on heart rate and blood pressure, plus anxiety and insomnia.
• PDE5 inhibitors + nitrates or nitrites: potentially dangerous drops in blood pressure.
• Anabolic steroids + stimulants: a common “cutting” mix that can increase cardiovascular strain while masking fatigue signals.
• Multiple hormones at once (testosterone + thyroid hormone + insulin, etc.): endocrine systems are not Lego sets. One change forces compensations elsewhere, and those compensations can be harmful.

People often assume that if each ingredient is “known,” the combination is safe. That’s not how pharmacology behaves in real bodies, especially when sleep, dehydration, and training stress are layered on top.

Myths and misinformation

Let’s clean up a few common myths I hear—sometimes from people who are otherwise very smart.

• Myth: “If it’s prescribed, it’s safe for anyone.” Reality: safety depends on diagnosis, dose, monitoring, and baseline risk. A medication can be appropriate for one person and dangerous for another.
• Myth: “You can ‘protect’ yourself with supplements.” Reality: supplements are not a substitute for clinical monitoring, and some add liver or cardiac risk. “Liver support” doesn’t neutralize hepatotoxic steroids.
• Myth: “Online labs and forums are basically medical care.” Reality: a lab value without context is a screenshot, not a plan. I often see people chasing numbers while ignoring symptoms—or the other way around.
• Myth: “PDE5 inhibitors are heart-safe because they’re common.” Reality: they are widely used and generally well-tolerated when prescribed appropriately, but interactions and contraindications are real, and counterfeit versions are a serious hazard.

If you want a deeper dive into misinformation patterns, see our guide to spotting risky health claims online.

Mechanism of action (in plain language, without the fairy tales)

Because “performance enhancement drugs” are diverse, the mechanisms differ. Still, they share a theme: they shift physiology toward a desired output—muscle protein synthesis, oxygen delivery, alertness, airway caliber, or blood flow—by acting on specific receptors or pathways.

Anabolic-androgenic steroids (example generic: testosterone)

Testosterone binds the androgen receptor, a nuclear receptor that influences gene transcription. In muscle, that signaling supports increased protein synthesis and changes in muscle fiber characteristics. In the brain, it can influence mood, libido, and energy. In the bone marrow, it can stimulate red blood cell production. That last effect is one reason hematocrit can rise.

When testosterone is used to correct true deficiency, the goal is physiologic replacement. When it’s used to exceed physiologic levels, downstream effects—lipids, blood pressure, cardiac remodeling, endocrine suppression—become more likely. The body adapts, and not always in a friendly way.

Erythropoiesis-stimulating agents (example generic: epoetin alfa)

Epoetin alfa is a synthetic form of erythropoietin signaling. It stimulates the bone marrow to produce more red blood cells. That improves oxygen-carrying capacity in anemia. In endurance misuse, the same effect can increase blood viscosity and thrombotic risk, especially when dehydration or altitude training enters the picture. Oxygen delivery is not just “more is better.” It’s a balance.

Stimulants (example generics: amphetamine, methylphenidate)

Stimulants increase signaling of neurotransmitters such as dopamine and norepinephrine in key brain circuits involved in attention and executive function. For ADHD, that can improve task initiation, working memory, and impulse control. For someone without ADHD chasing productivity, it can create a narrow tunnel of focus with collateral damage: anxiety, insomnia, appetite suppression, and cardiovascular strain.

PDE5 inhibitors (example generics: sildenafil, tadalafil)

PDE5 inhibitors block the enzyme phosphodiesterase type 5, which breaks down cGMP. By preserving cGMP signaling, they enhance smooth muscle relaxation and blood flow in specific vascular beds. For erectile dysfunction, they facilitate the normal physiologic pathway that responds to sexual stimulation; they do not create desire out of thin air. For pulmonary arterial hypertension, they support vascular relaxation in the pulmonary circulation under specialist care.

Historical journey

The history of performance enhancement drugs is basically the history of modern pharmacology colliding with human ambition. Each class has its own origin story, but the pattern repeats: a legitimate medical need drives development, then the non-medical world notices the side effects that look like “benefits.”

Discovery and development

Anabolic steroids trace back to early 20th-century endocrinology and the isolation and synthesis of testosterone. Clinicians needed ways to treat hypogonadism and wasting states. Athletes noticed the muscle effects. That wasn’t an accident; it was receptor biology doing what receptor biology does.

Erythropoiesis-stimulating agents emerged from advances in biotechnology and the need to treat anemia, especially in chronic kidney disease where endogenous erythropoietin production is impaired. Once endurance sports realized oxygen delivery could be pharmacologically manipulated, misuse followed. I’ve heard people describe it as “legal altitude.” It isn’t.

Stimulants have a long, complicated history in psychiatry and sleep medicine. Their legitimate role in ADHD and narcolepsy is supported by decades of clinical experience and research. Their misuse for studying, weight loss, or “grind culture” is equally old—and equally prone to dependence patterns.

PDE5 inhibitors became household names after sildenafil’s development and approval for erectile dysfunction, with later expansion into pulmonary hypertension indications. Their cultural visibility is enormous; patients joke about them, then whisper about them in the same breath. That stigma is real, and it shapes how people seek care.

Regulatory milestones

Regulators generally approve these drugs for defined medical conditions with measurable outcomes: hemoglobin targets, symptom scales, pulmonary pressures, diagnostic criteria for ADHD, and so on. Sports regulators, by contrast, focus on fairness and safety, leading to prohibited lists and therapeutic use exemptions. Those two systems overlap but do not share the same goal. One treats disease. The other polices competition.

From a clinician’s chair, the most meaningful “milestone” is not a headline approval date—it’s the establishment of monitoring standards: blood pressure checks, lab surveillance, contraindication screening, and follow-up. That boring infrastructure prevents a lot of harm.

Market evolution and generics

Once patents expire, generics often improve access and reduce cost. That’s a public health win when the medication is used appropriately. It can also increase misuse when the barrier to acquisition drops or when counterfeiters exploit demand. I’ve had patients bring in blister packs that looked legitimate until you held them next to the real thing. The details were off. The risk was not.

Society, access, and real-world use

Performance enhancement drugs don’t exist in a vacuum. They exist in workplaces that reward output, sports cultures that reward winning, and social media feeds that reward aesthetics. On a daily basis I notice how often people underestimate the psychological pressure piece. They talk about receptors and cycles, then admit they started because they felt “average.” That’s not a lab value.

Public awareness and stigma

Some performance-related medications have reduced stigma by making treatment more visible. Erectile dysfunction, for example, is discussed more openly than it was decades ago, partly because PDE5 inhibitors normalized the conversation. At the same time, visibility creates new stigma: people fear being judged for needing a medication, so they self-treat in secret. Patients tell me they’d rather risk an online pill than have an awkward appointment. I understand the emotion. I dislike the outcome.

ADHD treatment has a similar split. Legitimate patients can feel scrutinized, while misuse is normalized in certain circles. That dynamic harms everyone: it increases diversion risk and makes appropriate care harder to access.

Counterfeit products and online pharmacy risks

Counterfeits are not just “weaker than advertised.” They can contain the wrong dose, the wrong drug, contaminants, or nothing at all. The danger is amplified for drugs where dose and interactions matter—PDE5 inhibitors, stimulants, and hormones included.

Practical, safety-oriented guidance (without turning this into shopping advice): be wary of products that promise prescription-level effects without a prescription, that use vague ingredient lists, or that rely on influencer testimonials instead of regulated supply chains. If a site sells “pharma-grade” everything with no medical screening, that’s not convenience; that’s a red flag with a checkout button.

For more on avoiding dangerous products, our page on counterfeit medication warning signs is a useful companion read.

Generic availability and affordability

Generic drugs are required to meet quality standards for bioequivalence in regulated markets. When obtained through legitimate channels, generics are generally expected to perform similarly to brand-name versions for approved uses. The confusion starts when people equate “generic” with “anything cheap online.” Those are different universes.

Affordability also shapes behavior. When legitimate care feels expensive or inaccessible, people look for shortcuts. That’s a systems problem, not a moral failure. Still, the body doesn’t negotiate with the healthcare system; it reacts to what you put into it.

Regional access models (prescription, pharmacist-led, OTC)

Access rules vary widely by country and even by region within a country. Some places allow pharmacist-led access for certain medications; others require physician prescriptions; others have tighter controls due to misuse potential. Travel adds another layer: people buy abroad, assume equivalence, and return with products that don’t match domestic formulations or quality controls.

If you’re reading this from the perspective of “What’s allowed where?” the safest general principle is simple: treat access rules as safety infrastructure, not bureaucracy. When someone bypasses that infrastructure, they also bypass screening for contraindications and interactions.

Conclusion

Performance enhancement drugs include several legitimate medications—testosterone for confirmed hypogonadism, stimulants for ADHD, PDE5 inhibitors for erectile dysfunction or pulmonary hypertension, erythropoiesis-stimulating agents for anemia, and bronchodilators for asthma. In the right patient, under supervision, these therapies can be life-changing. In the wrong context, they can be quietly destructive.

The myths are seductive: “clean gains,” “safe stacks,” “just a little boost.” Real physiology is less forgiving. Blood pressure rises. Sleep fragments. Hormone axes shut down. Clotting risk shifts. Mood changes. Sometimes the consequences show up months later, when the original goal has already moved on.

Informational disclaimer: This article is for education only and does not replace individualized medical advice, diagnosis, or treatment. If you’re considering or already using any performance-related medication or hormone—prescribed or not—bring the full list to a qualified clinician and discuss risks, interactions, and safer alternatives.