Bipolar Affective Disorder (also known as bipolar disorder) is a chronic psychiatric illness. Patients experience alternating episodes of mania (elevated mood, excessive energy) and depression (low mood, loss of motivation). This emotional “swing between extremes” not only causes suffering but also profoundly impacts work, studies, relationships, and daily functioning.
In Hong Kong, as society pays increasing attention to mental health, more people are beginning to understand that bipolar disorder is not a “personality problem” or “weak willpower,” but a medical condition requiring professional treatment. Medication plays a central role in the treatment process. For moderate to severe patients, medication can effectively regulate neurotransmitters in the brain, stabilize mood, and reduce both manic and depressive episodes.
However, public misconceptions remain: some worry that “medications are addictive,” others fear they “change personality,” and some resist treatment due to side effects. They work scientifically to restore balance in brain chemistry. Under the supervision of a psychiatrist, medication can significantly improve quality of life and reduce relapse risk.
Part I: Mood Stabilizers
Why Mood Stabilizers Are the Cornerstone of Treatment
Mood stabilizers are the core medications for bipolar disorder. Their main function is to reduce the frequency and intensity of manic and depressive episodes, helping patients maintain emotional balance. Unlike antidepressants, mood stabilizers do not only target depressive symptoms; they also prevent the recurrence of both manic and depressive extremes.
Clinical studies show that relying solely on antidepressants may trigger mania or accelerate mood swings. Therefore, mood stabilizers are often the first‑line treatment, combined with other medications when necessary.
1. Lithium
Mechanism of Action
Lithium is the earliest and most widely used mood stabilizer, still regarded as the “gold standard.” It regulates multiple neurotransmitters in the brain, including serotonin, norepinephrine, and dopamine, thereby stabilizing mood.
Advantages
- Effective for both mania and depression, reducing relapse rates.
- Research shows it can lower suicide risk.
- Over 50 years of clinical use, with well‑established safety and efficacy.
Disadvantages & Side Effects
- Requires regular blood tests to monitor lithium levels and avoid toxicity.
- Common side effects: thirst, frequent urination, tremor, weight gain.
- Long‑term use may affect kidney and thyroid function.
Indications
- Suitable for most bipolar patients, especially those at suicide risk.
- Particularly effective for recurrent episodes.
2. Valproate
Mechanism of Action
Valproate enhances gamma‑aminobutyric acid (GABA) activity, suppressing excessive neuronal excitation and stabilizing mood.
Advantages
- Particularly effective for manic symptoms.
- Rapid onset, suitable for acute treatment.
- Useful for patients with anxiety or impulse control difficulties.
Disadvantages & Side Effects
- Common side effects: weight gain, drowsiness, gastrointestinal upset.
- Requires monitoring of liver function and platelet count.
- Not suitable for pregnant women due to risk of fetal malformations.
Indications
- Suitable for acute manic episodes.
- For patients who respond poorly to or cannot tolerate lithium.
3. Carbamazepine
Mechanism of Action
Originally used for epilepsy, carbamazepine was later found to stabilize mood in bipolar disorder. It suppresses excessive neuronal firing, reducing mood fluctuations.
Advantages
- Effective for mania and mixed episodes.
- Suitable for patients unresponsive to lithium or valproate.
Disadvantages & Side Effects
- May cause dizziness, drowsiness, gastrointestinal upset.
- Requires monitoring of liver function and blood counts.
- Multiple drug interactions; must be used cautiously.
Indications
- Suitable for treatment‑resistant bipolar disorder.
- Helpful for patients with impulsivity or aggressive behavior.
4. Lamotrigine
Mechanism of Action
Lamotrigine is mainly used to prevent depressive episodes. It stabilizes neuronal membranes and reduces glutamate release, thereby lowering mood fluctuations.
Advantages
- Particularly effective for bipolar depression.
- Fewer side effects; does not cause weight gain.
- Suitable for long‑term maintenance therapy.
Disadvantages & Side Effects
- Requires slow dose titration to avoid rash (including rare but serious Stevens–Johnson syndrome).
- Limited effect in acute mania.
Indications
- Suitable for patients with predominantly depressive episodes.
- Appropriate for long‑term maintenance.
Part II: Antipsychotics
First‑Generation vs. Second‑Generation Antipsychotics
Antipsychotics were originally developed for schizophrenia, but research shows they are also effective in bipolar disorder.
First‑Generation (Typical) Antipsychotics
- Examples: Haloperidol, Chlorpromazine.
- Mechanism: Strong dopamine receptor blockade, rapidly controlling mania.
- Disadvantages: Significant side effects, including extrapyramidal symptoms (tremor, rigidity, slowed movement) and tardive dyskinesia.
Second‑Generation (Atypical) Antipsychotics
- Examples: Olanzapine, Quetiapine, Risperidone, Aripiprazole.
- Mechanism: Act on both dopamine and serotonin receptors, providing broader effects.
- Advantages: Fewer side effects, beneficial for mood stabilization and depressive symptoms.
- Disadvantages: Metabolic side effects (weight gain, elevated blood sugar, cholesterol abnormalities).
Second‑generation antipsychotics have become mainstream in bipolar treatment, especially in Hong Kong and international guidelines, for both acute mania and maintenance therapy.
Olanzapine
- Mechanism: Blocks dopamine D2 and serotonin 5‑HT2 receptors, rapidly controlling mania.
- Uses: Acute mania, maintenance, combined with antidepressants for bipolar depression.
- Side Effects: Significant weight gain, metabolic syndrome risk, drowsiness.
- Monitoring: Regular checks of weight, blood sugar, lipids.
Quetiapine
- Mechanism: Multi‑receptor action, effective for both mania and depression.
- Uses: Acute mania, bipolar depression, maintenance.
- Side Effects: Drowsiness, weight gain, metabolic abnormalities.
- Monitoring: Regular metabolic screening.
Risperidone
- Mechanism: Blocks dopamine and serotonin receptors.
- Uses: Acute mania, maintenance.
- Side Effects: Weight gain, elevated prolactin (may cause gynecomastia in men, menstrual irregularities in women).
- Monitoring: Prolactin levels.
Aripiprazole
- Mechanism: Partial dopamine agonist, balancing dopamine activity.
- Uses: Acute mania, maintenance.
- Side Effects: Restlessness, insomnia, fewer metabolic effects.
- Monitoring: Mental state and sleep.
Lurasidone
- Mechanism: Acts on dopamine D2, serotonin 5‑HT2A, and 5‑HT7 receptors, improving mood and cognition.
- Uses: FDA‑approved for bipolar depression, also helpful for anxiety.
- Side Effects: Nausea, insomnia, agitation, drowsiness, dizziness.
- Monitoring: Mental state and sleep.
Part III: Antidepressants in Bipolar Disorder
Why Must They Be Combined with Mood Stabilizers?
Antidepressants improve depressive symptoms, but in bipolar patients, using them alone may trigger mania or accelerate mood swings. Therefore, they must be combined with mood stabilizers or antipsychotics to reduce risk.
Representative Medications
- SSRIs (Selective Serotonin Reuptake Inhibitors)
- Examples: Sertraline, Escitalopram.
- Advantages: Fewer side effects, well tolerated.
- Disadvantages: May trigger mania.
- SNRIs (Serotonin–Norepinephrine Reuptake Inhibitors)
- Examples: Venlafaxine, Duloxetine.
- Advantages: Improve mood and motivation.
- Disadvantages: More side effects, require gradual tapering.
Risks: Triggering Mania
- Antidepressants alone may cause mania or mixed episodes.
- Must always be combined with mood stabilizers or antipsychotics.
Indications & Precautions
- Suitable for patients with predominant depressive symptoms.
- Must be supervised by a psychiatrist; avoid monotherapy.
- Regular monitoring of mood to detect early signs of mania.
Part IV: Other Medications and Adjunctive Treatments
Benzodiazepines
- Mechanism: Enhance GABA activity, calming the nervous system.
- Uses: Acute mania (reduce agitation, insomnia, impulsivity), short‑term anxiety relief, insomnia.
- Advantages: Rapid onset, convenient.
- Disadvantages: Risk of dependence with long‑term use, side effects include drowsiness, memory impairment, slowed reactions.
- Clinical Note: Only for short‑term use; psychiatrists taper gradually.
Part V: Treatment Process and Clinical Considerations
Initiation of Treatment
- Psychiatrists select medications based on the patient’s current phase (mania or depression), medical history, and physical condition.
- Acute mania: Antipsychotics are commonly used for rapid control.
- Depressive phase: Quetiapine or lamotrigine are often chosen, in combination with antidepressant.
- Mixed episodes: Combination therapy may be required.
Dose Adjustment
- Treatment usually begins with a low dose, gradually increased to therapeutic levels.
- Adjustments depend on clinical response and side effects.
- Close monitoring ensures balance between efficacy and tolerability.
Duration of Treatment
- Most patients require at least 12 months of continuous treatment after an episode.
- Many will need long‑term or lifelong maintenance therapy to prevent relapse.
- Stopping medication prematurely greatly increases the risk of recurrence.
Principles of Discontinuation
- Medications must never be stopped abruptly; sudden withdrawal can trigger relapse or withdrawal symptoms.
- Tapering should be gradual, under medical supervision.
- Discontinuation decisions are individualized, based on stability, history, and risk factors.
Regular Monitoring
- Blood tests: Liver function, kidney function, blood counts, and drug levels (e.g., lithium).
- Metabolic monitoring: Weight, blood sugar, cholesterol, blood pressure.
- Mental state evaluation: Regular psychiatric assessments to track mood, cognition, and functioning.
- Side effect surveillance: Early detection allows timely intervention.
Part VI: Frequently Asked Questions (FAQ)
- Are bipolar medications addictive?
- Mood stabilizers, antipsychotics, and antidepressants are not addictive.
- Benzodiazepines may cause dependence if misused long‑term, but psychiatrists prescribe them cautiously and usually short‑term.
- How long do I need to take medication?
- At least 12 months after an episode is recommended.
- Many patients require long‑term maintenance to prevent relapse.
- Duration varies depending on individual history and risk factors.
- How can side effects be managed?
- Most side effects improve over time.
- Psychiatrists can adjust dosage or switch medications if necessary.
- Regular monitoring helps detect and address problems early.
- Lifestyle adjustments (diet, exercise, sleep hygiene) can reduce metabolic side effects.
- Can I rely only on psychotherapy?
- Psychotherapy is valuable for coping skills, stress management, and relationships.
- But for moderate to severe bipolar disorder, medication is essential.
- Best outcomes come from combining medication, psychotherapy, and lifestyle changes.
Psychiatrist’s Key Reminders
- Medication is only one part of treatment: Optimal recovery requires integration of medication, psychotherapy, and lifestyle modification.
- Family and social support are crucial: Involving loved ones improves adherence and outcomes.
- Reduce stigma: Bipolar disorder is a medical condition, not a personality flaw.
- Seek help early: Prompt treatment reduces relapse risk and complications.
