Lithium (take 12 hours after dose)

What is the Lithium test?

The Lithium blood test measures the concentration of lithium in the bloodstream. Lithium is a medication most commonly used in the treatment of bipolar disorder and certain mood disorders.

Lithium has a narrow therapeutic range, meaning the difference between an effective dose and a toxic dose is small. Regular monitoring ensures levels remain within a safe and effective range.

This test is a standard part of psychiatric medication management and long-term treatment safety.

Why do I need a Lithium test?

Lithium levels can be affected by hydration, kidney function, medication interactions, and illness. Monitoring prevents serious side effects.

You may need a Lithium test if you:

• Are taking lithium for bipolar disorder
• Have recently started lithium therapy
• Have had a dose change
• Experience side effects or symptoms of toxicity
• Have kidney function changes
• Are unwell, dehydrated, or vomiting
• Require routine treatment monitoring

Symptoms associated with abnormal lithium levels include:

• Tremor
• Nausea or vomiting
• Diarrhoea
• Confusion or drowsiness
• Poor coordination
• Excessive thirst or urination

Benefits of the Lithium test

·       Ensures safe lithium therapy
Prevents under- or over-dosing.

·       Detects lithium toxicity early
Reduces risk of serious complications.

·       Guides dose adjustments
Supports effective mood stabilisation.

·       Essential for long-term treatment
Required for ongoing lithium use.

·       Clinically standard monitoring test
Used in psychiatry worldwide.

·       Supports kidney safety
Helps detect lithium accumulation.

·       Useful during illness or dehydration
Identifies increased toxicity risk.

·       Simple blood test
Requires only one blood sample.

Step by step – how the test works

You can access Lithium testing UK-wide through two options:

1. Clinic appointment
   Attend your nearest UK clinic for a blood draw, usually taken 12 hours after the last dose (trough level).
2. At-home or hotel visit (£60 extra)
   A qualified phlebotomist comes to your home or hotel, maintaining correct timing.

Your sample is analysed in an accredited UK laboratory and results are delivered securely.

Your results explained

Low lithium level

May be sub-therapeutic and less effective.

Typical UK interpretation:

• < 0.4 mmol/L

Therapeutic lithium level

Within the effective and safe treatment range.

Typical UK interpretation:

• 0.4 – 1.0 mmol/L
  (Target range depends on clinical indication)

High lithium level

Indicates lithium toxicity risk and requires urgent review.

Typical UK interpretation:

• > 1.0 mmol/L

Timing of blood draw is critical for accurate interpretation.