Biomedical Therapies and Treatment Evaluation

1. Psychopharmacology: The Major Drug Classes

Biomedical therapy acts directly on the body's physiology. Psychopharmacology is the study and use of drugs affecting mind and behavior:

• Antipsychotics — for schizophrenia spectrum and related psychoses; many reduce dopamine activity (reflecting the dopamine hypothesis). Older "typical" drugs can cause movement side effects; newer "atypical" drugs target multiple receptors.
• Antidepressants — for depression and several anxiety disorders; many act on serotonin and/or norepinephrine systems (e.g., SSRIs), often taking weeks to work.
• Anti-anxiety medications — reduce acute anxiety (e.g., benzodiazepines, which enhance the inhibitory neurotransmitter GABA); fast-acting but with risks of tolerance and dependence.
• Mood stabilizers — for bipolar disorder, preventing or reducing mood episodes (e.g., lithium and some anticonvulsants).

2. Mechanism Concepts and Side Effects

A drug's mechanism is how it works biologically — for example, blocking reuptake of a neurotransmitter (leaving more in the synapse) or binding a receptor. Side effects are unintended effects from acting on systems beyond the target (weight gain, sedation, movement problems). Because individuals metabolize drugs differently, dosing is individualized and benefits are weighed against side effects over time.

3. Brain Stimulation and Treatment Evaluation

Electroconvulsive therapy (ECT) applies brief electrical currents to induce a controlled seizure under anesthesia; it is highly effective for severe, treatment-resistant depression but can cause short-term memory loss and carries historical stigma. Transcranial magnetic stimulation (TMS) uses magnetic pulses on the scalp to stimulate specific brain regions; it is non-invasive, needs no anesthesia, and is used for depression unresponsive to other treatments.

Efficacy asks whether a treatment works under ideal, controlled conditions (randomized controlled trials, or RCTs); effectiveness asks whether it works in real-world practice. A placebo is an inactive treatment controlling for expectancy; RCTs compare an active treatment against placebo to isolate its true effect. Evidence-based care integrates this research with clinical judgment and patient values, using risk–benefit analysis (weighing benefits against harms) and informed consent (understanding and agreeing to purpose, risks, and alternatives).

How it works

1. A qualified prescriber assesses the person (diagnosis, history, preferences).
2. A treatment (medication and/or brain stimulation) is selected based on evidence.
3. Risks, benefits, and alternatives are explained (informed consent).
4. Treatment is started, monitored, and adjusted for response and side effects.
5. It is combined with psychotherapy and lifestyle support in a biopsychosocial plan.

Common confusions

Memory aids

Drug classes: "A-A-A-M" — Antipsychotics, Antidepressants, Anti-anxiety, Mood stabilizers. Evaluation: "E-E-R-P" — Efficacy, Effectiveness, RCTs, Placebo.

Quick review

Topic Recap

Biomedical therapy acts on the body, primarily through psychopharmacology: antipsychotics, antidepressants, anti-anxiety drugs, and mood stabilizers, each with distinct mechanisms and side effects. Brain-stimulation treatments — ECT and TMS — offer options for difficult-to-treat depression. Treatment decisions rely on RCT and placebo evidence, distinguishing efficacy from effectiveness, and balancing risk against benefit through informed consent and prescriber supervision. All of this is educational; actual treatment requires qualified professionals.

Knowledge Check

1. What is the difference between efficacy and effectiveness?
2. Why do RCTs support causal claims where correlational studies cannot?
3. Which drug class is primarily used for bipolar disorder, and what is a classic example?
4. How do ECT and TMS differ?
5. Why is informed consent essential for biomedical treatments?

Answers and Rationales

1. Efficacy is whether a treatment works under ideal, controlled conditions; effectiveness is whether it works in real-world practice.
2. RCTs use random assignment, which balances unknown factors so differences can be attributed to the treatment (causation); correlational designs cannot rule out third variables.
3. Mood stabilizers; lithium is the classic example.
4. ECT induces a controlled seizure under anesthesia using electrical current; TMS delivers magnetic pulses through the scalp and is non-invasive with no anesthesia.
5. These treatments act on the body and carry risks and side effects, so a person must understand the purpose, risks, and alternatives before agreeing.