Bipolar Mood Disorder is a chronic, recurrent psychiatric illness characterized by episodes of mania, hypomania, depression, or mixed affective states. The disorder follows an episodic and variable course, causing disturbances in mood regulation, energy, cognition, behaviour, and psychosocial functioning.

A diagnosis of bipolar disorder requires the presence of at least one current or previous episode of mania or hypomania. The condition is associated with significant morbidity, impaired occupational and social functioning, increased medical comorbidity, and increased risk of suicide.

Epidemiology

• Lifetime prevalence is approximately 1–3% worldwide.

• Occurs in both males and females.

• Usual age of onset is late adolescence or early adulthood.

• The disorder has a high recurrence rate, with many patients experiencing repeated episodes during their lifetime.

• Bipolar disorder contributes substantially to global psychiatric disability.

• Suicide risk is significantly increased compared with the general population.

Risk factors

Genetic factors

• Strong hereditary component.

• Family history of bipolar disorder.

• First-degree relatives have increased risk.

• Polygenic inheritance pattern.

Neurobiological factors

• Dysregulation of dopamine, serotonin, and glutamate pathways.

• Circadian rhythm disturbances.

• Structural and functional brain abnormalities.

Psychological factors

• Stress sensitivity.

• Personality vulnerabilities.

• Poor coping mechanisms.

Environmental and social factors

• Psychosocial stressors.

• Sleep deprivation.

• Substance misuse.

• Major life transitions.

Pathophysiology

Bipolar disorder results from complex interactions between genetic vulnerability, neurobiological dysfunction, and environmental factors.

Major mechanisms include:

• Abnormal regulation of neurotransmitters including dopamine, serotonin, and glutamate.

• Altered intracellular signalling pathways.

• Impaired neuroplasticity mechanisms.

• Dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis.

• Disturbance of circadian rhythm control systems.

These abnormalities result in instability of mood regulation networks, leading to alternating episodes of mania, depression, and mixed states.

Clinical types

Bipolar I Disorder

• Characterized by at least one manic episode, with or without depressive episodes.

Bipolar II Disorder

• Characterized by hypomanic episodes and major depressive episodes without full mania.

Cyclothymic Disorder

• Chronic fluctuating mood symptoms that do not meet criteria for full manic or depressive episodes.

Rapid cycling bipolar disorder

• Four or more mood episodes occurring within one year.

Clinical presentation

Patients may present with manic, hypomanic, depressive, or mixed episodes. Symptoms vary between individuals and may change throughout the course of illness.

Symptoms

Manic episode

A manic episode is characterized by a period of at least 1 week of persistently elevated, expansive, or irritable mood present most of the day, nearly every day.

Associated symptoms include:

• Increased self-confidence or grandiosity.

• Grandiose or religious delusions.

• Reduced need for sleep.

• Increased talkativeness and pressure to speak.

• Racing thoughts.

• Distractibility.

• Increased goal-directed activity.

• Excessive involvement in activities with potential harmful consequences.

• Increased energy.

• Poor judgement.

• Irritability or aggression.

The episode causes marked impairment in functioning, may require hospitalization, or may include psychotic features.

Hypomanic episode

Symptoms are similar to mania but are:

• Less severe.

• Not associated with marked functional impairment.

• Without psychosis.

• Usually not requiring hospitalization.

Depressive episode

Symptoms include:

• Persistent low mood.

• Loss of interest or pleasure.

• Fatigue.

• Sleep disturbance.

• Appetite changes.

• Feelings of guilt or hopelessness.

• Poor concentration.

• Suicidal thoughts.

Mixed episode

Mixed features occur when manic and depressive symptoms occur together, including:

• Agitation with sadness.

• Irritability.

• Insomnia.

• Increased energy with depressive symptoms.

• Increased suicide risk.

Clinical signs

• Elevated or irritable mood.

• Pressured speech.

• Increased psychomotor activity.

• Reduced need for sleep.

• Distractibility.

• Grandiose ideas.

• Risk-taking behaviour.

• Poor judgement.

• Psychotic features such as delusions or hallucinations.

• Depressed mood and psychomotor slowing during depressive episodes.

• Functional impairment in social, occupational, or interpersonal activities.

Differential diagnosis

• Major depressive disorder.

• Schizoaffective disorder.

• Schizophrenia with mood symptoms.

• Substance-induced mood disorder.

• Attention deficit hyperactivity disorder (ADHD).

• Personality disorders.

• Thyrotoxicosis.

• Drug intoxication.

• Medical conditions causing mood disturbance.

Diagnostic criteria

Diagnosis is based on DSM-5 criteria.

Bipolar I Disorder

Requires at least one manic episode.

Manic episode criteria

A distinct period of abnormally and persistently elevated, expansive, or irritable mood and increased energy/activity lasting:

• At least 1 week, or requiring hospitalization.

During this period, at least 3 symptoms (or 4 if mood is only irritable) must be present:

• Inflated self-esteem or grandiosity.

• Decreased need for sleep.

• Increased talkativeness.

• Flight of ideas or racing thoughts.

• Distractibility.

• Increased goal-directed activity.

• Excessive involvement in risky activities.

The episode causes:

• Marked impairment in functioning.

• Hospitalization.

• Psychotic features.

Symptoms must not be due to substance use or another medical condition.

Investigations

Purpose

Investigations aim to:

• Exclude medical and substance-related causes.

• Establish baseline parameters before treatment.

• Monitor medication safety.

Baseline investigations

• Full blood picture (FBP).

• Renal function tests (RFT).

• Liver function tests (LFT).

• Thyroid function tests (TFT).

• Serum electrolytes.

• Blood glucose.

• Toxicology screening.

• Pregnancy test where applicable.

Monitoring investigations

• Lithium serum levels where lithium therapy is used.

• Valproate levels where indicated.

• Renal function monitoring.

• Thyroid function monitoring.

• Liver function monitoring.

Management

Management aims to:

• Control acute episodes.

• Prevent relapse.

• Restore functioning.

• Reduce suicide risk.

• Provide long-term psychosocial support.

Initial management includes:

• Assess risk of suicide or harm to others.

• Assess severity of mania or depression.

• Exclude medical and substance-related causes.

• Manage agitation and behavioural disturbance.

• Initiate mood stabilizing treatment.

Non-pharmacological treatment

Acute phase

• Hospitalization may be required during severe mania, severe depression, psychosis, or suicide risk.

• Reduce environmental stimulation.

• Restore normal sleep patterns.

• Ensure patient safety.

Psychosocial interventions

• Psychoeducation for patient and family.

• Family therapy.

• Cognitive Behavioural Therapy (CBT).

• Supportive psychotherapy.

• Interpersonal and social rhythm therapy.

• Medication adherence counselling.

Other interventions

• Electroconvulsive therapy (ECT) may be required for:

  • Severe mania.

  • Treatment-resistant episodes.

  • Psychotic depression.

  • Severe suicidal emergencies.

Pharmacological treatment

Management of manic or mixed episodes

For agitated and acutely disturbed patients:

Manage according to the Aggressive and Disruptive Behaviours guideline.

Maintenance therapy

Mood stabilizers

• Carbamazepine – 600 mg – PO – every 24 hours in 2–3 divided doses; increase by 200 mg at 3-day intervals up to a maximum dose of 2000 mg/day.

OR

• Sodium valproate – 20 mg/kg/day – PO – in 2–3 divided doses (maximum dose: 2000 mg/day).

OR

• Lamotrigine – 600 mg – PO – once daily; increase by 200 mg at 3-day intervals up to a maximum dose of 2000 mg.

Note

• Combination therapy with two mood stabilizers may be considered at specialist level, for example sodium valproate and lithium carbonate.

• Monitor treatment response and adverse effects regularly.

Treatment for severe depressive episodes in bipolar patients

Antidepressants should not be used as monotherapy in bipolar patients.

Give antidepressant therapy together with a mood stabilizer and add an antipsychotic if psychotic symptoms are present.

• Amitriptyline – 12.5–50 mg – PO – nocte.

OR

• Fluoxetine – 10–20 mg – PO – nocte.

AND

• Carbamazepine – 200–400 mg – PO – every 12 hours (maximum dose: 2000 mg/day).

OR

• Sodium valproate – 500–2000 mg – PO – every 24 hours.

If psychosis is present:

• Chlorpromazine – 100–1000 mg – PO – every 24 hours in divided doses (maximum dose: 1000 mg/day).

OR

• Haloperidol – 1.5–10 mg – PO – every 12 hours.

Note

• Symptoms should be monitored and medication tapered according to clinical response.

Management according to underlying episode

Acute mania

• Ensure safety.

• Consider hospitalization.

• Treat agitation according to aggressive and disruptive behaviour guidelines.

• Initiate mood stabilizer therapy.

Bipolar depression

• Avoid antidepressant monotherapy.

• Combine antidepressants with mood stabilizers.

• Monitor closely for mood switching into mania.

Rapid cycling bipolar disorder

• Refer for specialist psychiatric management.

• Review medication adherence and possible triggers.

Referral

Refer to specialist psychiatric care in the following situations:

• Mixed bipolar disorder.

• Rapid cycling bipolar disorder.

• Manic episodes not responding to treatment.

• Depressive episodes not responding to treatment.

• Severe suicidal risk.

• Psychotic symptoms.

• Diagnostic uncertainty.

• Severe medication adverse effects.

• Pregnancy or breastfeeding.

• Children and adolescents.

Complications

• Suicide.

• Substance misuse.

• Psychosis.

• Cognitive impairment.

• Occupational dysfunction.

• Relationship difficulties.

• Social isolation.

• Recurrent hospitalization.

• Medication toxicity.

• Poor adherence.

Prognosis

Bipolar disorder is a lifelong condition with recurrent episodes. However, good outcomes can be achieved with:

• Early diagnosis.

• Long-term mood stabilizer therapy.

• Good medication adherence.

• Family support.

• Regular psychiatric follow-up.

Poor outcomes are associated with:

• Frequent relapses.

• Substance misuse.

• Poor adherence.

• Persistent symptoms.

• Severe psychosocial impairment.

Prevention

Relapse prevention includes:

• Long-term maintenance mood stabilizer therapy.

• Early recognition of relapse symptoms.

• Maintaining regular sleep patterns.

• Stress reduction.

• Avoidance of alcohol and recreational substances.

• Family education and support.

• Regular psychiatric review.

Patient and Family Education

Patients and caregivers should understand that:

• Bipolar disorder is chronic but manageable.

• Medication adherence is essential.

• Sleep deprivation can trigger manic episodes.

• Early warning signs should prompt medical review.

• Alcohol and recreational drugs may worsen symptoms.

• Regular follow-up improves long-term outcomes.