Meta Information
ID:lithium-microdose
Name:Microdosing Lithium
Schema Version:2.4_uniform_evidence_2026_06_18
Interactions
Target id:
/condition/pregnancy
Target name:
Pregnancy
Severity:
major
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
Lithium can cross the placenta and has been linked to birth defects, particularly cardiac malformations (Ebstein's anomaly).
Actionable advice:
This should be strictly avoided during pregnancy or if planning to become pregnant.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
Lithium completely equilibrates across the placenta.
Label source:
PubMed: 16263858
Source url:
Exact phrase from label:
Lithium, used for treating bipolar disease, crosses freely the placenta and is classified as teratogenic.
Label source:
PubMed: 25645381
Action type:
avoid
Target id:
/condition/breastfeeding
Target name:
Breastfeeding
Severity:
major
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
Lithium is excreted into breast milk and can reach significant concentrations, posing a risk of toxicity to the nursing infant.
Actionable advice:
It should be avoided completely while breastfeeding.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
Drugs contraindicated during breastfeeding include anticancer drugs, lithium, oral retinoids, iodine, amiodarone and gold salts.
Label source:
PubMed: 26648652
Source url:
Exact phrase from label:
Breastfeeding should be avoided while using lithium.
Label source:
PubMed: 16529525
Action type:
avoid
Target id:
/condition/hypothyroidism
Target name:
Hypothyroidism
Severity:
moderate
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
Lithium can interfere with thyroid hormone production and release, potentially causing or exacerbating hypothyroidism.
Actionable advice:
Thyroid function (TSH) should be monitored periodically in those with a history of thyroid issues or taking lithium long-term.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
The prevalence of clinical hypothyroidism was increased in patients taking lithium compared with those given placebo (odds ratio [OR] 5·78, 95% CI 2·00-16·67; p=0·001), and thyroid stimulating hormone was increased on average by 4·00 iU/mL (95% CI 3·90-4·10, p<0·0001).
Label source:
PubMed: 22265699
Source url:
Exact phrase from label:
Out of the 46 patients, 8 (17%) displayed overt hypothyroidism. Of the remaining patients, subclinical hypothyroidism was found in 16 patients (35%) and euthyroidism in 22 (48%).
Label source:
PubMed: 16602451
Action type:
monitor
Target id:
/class/neuromuscular-blockers
Target name:
Neuromuscular Blocking Agents
Severity:
moderate
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
Lithium can enhance and prolong the muscle-relaxing effects of agents used during general anesthesia for surgery.
Actionable advice:
It is a good idea to let an anesthesiologist know about lithium use before any surgical procedure.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
Many drugs interact with neuromuscular blocking agents and there is often a potentiation of the neuromuscular effect. This is of clinical importance in the case of antibiotics, inhalational anaesthetics, lithium and cyclosporin.
Label source:
PubMed: 2682131
Action type:
informational_none
Target id:
/biomarker/egfr
Target name:
eGFR (Kidney Function)
Severity:
moderate
Interaction type:
requirement
Nature:
absolute
Temporal spacing:
null
Description:
Long-term lithium use, even at low doses, can potentially affect kidney function, which needs to be monitored for safety.
Actionable advice:
Periodically monitor kidney function (e.g., annually) via blood tests when taking lithium long-term.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
The lithium serum level (interpretable as "effect of LA") had a significant effect on eGFR decline.
Label source:
PubMed: 36585782
Source url:
Exact phrase from label:
Optimal management of lithium treatment requires obtaining a baseline measure of renal function (typically estimated glomerular filtration rate [eGFR]) and regular monitoring of eGFR during treatment.
Label source:
PubMed: 37971552
Action type:
monitor
Target id:
/biomarker/tsh
Target name:
TSH (Thyroid Function)
Severity:
moderate
Interaction type:
requirement
Nature:
absolute
Temporal spacing:
null
Description:
Lithium can impact thyroid function, so regular monitoring of Thyroid-Stimulating Hormone (TSH) is recommended for long-term users.
Actionable advice:
Periodically monitor thyroid function (e.g., annually) via a TSH blood test.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
These results suggest that the risk of lithium-induced hypothyroidism is dose-related, and relatively small with very low doses, but thyroid monitoring, including a pre-lithium TSH, is still warranted.
Label source:
PubMed: 37704933
Source url:
Exact phrase from label:
If the patient shows normal thyroid function, TSH level measurement and thyroid ultrasound should be performed at 6- to 12-month intervals for long term.
Label source:
PubMed: 32633237
Action type:
monitor
Target id:
/dietary/sodium-rich-foods
Target name:
High-Sodium Foods
Severity:
minor
Interaction type:
diminishing
Nature:
absolute
Temporal spacing:
null
Description:
A sudden, large increase in sodium intake can increase lithium excretion by the kidneys, potentially reducing its levels and effectiveness.
Actionable advice:
A consistent sodium intake is generally best maintained, and sudden, large increases in salt consumption are best avoided.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
Volume expansion with 2 l 0.9% saline administered intravenously during a 4-hour period provoked an exaggerated natriuresis and a greater increase in fractional lithium clearance in hypertensive patients compared with the control group.
Label source:
PubMed: 2493425
Action type:
avoid
Target id:
/dietary/caffeinated-beverages
Target name:
Caffeinated Beverages (Coffee, Tea)
Severity:
minor
Interaction type:
diminishing
Nature:
absolute
Temporal spacing:
null
Description:
Caffeine has a mild diuretic effect that can increase the rate at which lithium is cleared from the body by the kidneys, slightly lowering its level.
Actionable advice:
Caffeine intake is generally best kept consistent from day to day to maintain stable lithium levels.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
When compared with the placebo day, caffeine caused increases in lithium clearance (experimental period values: caffeine, 37+/-1 ml/min; placebo, 28+/-2 ml/min; P <0.001), the fractional excretion of lithium (caffeine, 34+/-1%; placebo, 26+/-2%; P <0.001) and the sodium/lithium clearance ratio (used as an index of the fraction of sodium delivered to the distal nephron that escapes reabsorption therein: caffeine, 4.4+/-0.3%; placebo, 2.8+/-0.2%; P <0.001).
Label source:
PubMed: 12401118
Source url:
Exact phrase from label:
Most case reports described people with BD switching to manic, hypomanic or mixed states after consuming caffeine in variable amounts and/or whose serum lithium concentrations increased after reducing caffeine consumption.
Label source:
PubMed: 32949106
Action type:
informational_none
Target id:
/class/ssris-snris
Target name:
SSRI & SNRI Antidepressants
Severity:
major
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
Lithium can trigger serotonin syndrome — a potentially life-threatening reaction — when combined with SSRIs or SNRIs. Although most reported cases involved full therapeutic lithium doses, the FDA label flags this combination as a serious concern, so a microdose does not eliminate the warning.
Actionable advice:
This should not be combined without prescriber oversight. If co-administration is unavoidable, it is worth watching out for agitation, confusion, tremor, rapid heart rate, sweating, or fever; lithium should be stopped and care sought if these appear.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
A 71-year-old woman developed serotonin syndrome while receiving treatment with moderate doses of lithium and venlafaxine for refractory depression.
Label source:
PubMed: 16882112
Source url:
Exact phrase from label:
Several case reports have engendered concern about the safety of coadministering lithium and selective serotonin reuptake inhibitor (SSRI) antidepressants and there are theoretical reasons to suppose that lithium and serotonergic antidepressants may be associated with dangerous interactions.
Label source:
PubMed: 10954059
Action type:
avoid
Target id:
/class/antipsychotics
Target name:
Antipsychotic Medications
Severity:
major
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
Lithium taken with an antipsychotic has been linked to a rare but serious neurotoxic reaction (encephalopathy with confusion, fever, tremor, and stiffness) that in some cases left lasting damage. The cases were at therapeutic lithium doses, but the FDA label treats this combination as a meaningful safety signal.
Actionable advice:
Coordinate with the prescriber before combining. If used together, monitor for new tremor, muscle rigidity, lethargy, confusion, or fever and stop lithium and seek evaluation if these appear.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
The mutual enhancement of the side effects of muscular tremor and rigidity caused by lithium and neuroleptic drugs should be recognised.
Label source:
PubMed: 6126349
Action type:
monitor
Target id:
/intervention/iodine
Target name:
Iodine
Severity:
minor
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
Lithium can interfere with the thyroid's use of iodine; ensuring adequate iodine intake may help mitigate the risk of hypothyroidism.
Actionable advice:
An adequate dietary intake of iodine (e.g., from iodized salt or seaweed) is generally best maintained.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
Lithium is concentrated by the thyroid and inhibits thyroidal iodine uptake.
Label source:
PubMed: 9827658
Action type:
informational_none
Target id:
/dietary/meal
Target name:
Any Caloric Food or Meal
Severity:
minor
Interaction type:
informational
Nature:
temporal
Temporal spacing:
Hours before target:
0
Hours after target:
0
Description:
Taking lithium with food can help reduce potential gastrointestinal side effects like nausea or stomach upset.
Actionable advice:
A dose is generally best taken with a meal or snack to improve tolerability.
Validation status:
validated_via_pubmed
Evidence tier:
tier_b
Evidence basis:
pubmed_abstract_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
Postprandial administration of lithium gave practically no side effects, while lithium on an empty stomach gave diarrhoea in about 20% of the subjects.
Label source:
PubMed: 1096537
Action type:
informational_none
Derived From
microdosing-lithium
Provenance Note
Interactions duplicated from 'microdosing-lithium'. Microdose lithium; same interactions.