Case reports and several retrospective studies have demonstrated possible increases in the rate of a congenital heart defect known as Ebsteins anomaly, if taken during a womans pregnancy. As a consequence, fetal echocardiography is routinely performed in pregnant women taking lithium to exclude the possibility of cardiac anomalies. Lamotrigine seems to be a possible alternative to lithium in pregnant women for the treatment of acute bipolar depression or for the management of bipolar patients with normal mood. Gabapentin and clonazepam are also indicated as  antipanic medications during the childbearing years and during pregnancy. Valproic acid and carbamazepine also tend to be associated with teratogenicity. While it appears to be safe to use while breastfeeding a number of guidelines list it as a contraindication including the British National Formulary. Kidney damage
Lithium has been associated with several forms of kidney injury. It is estimated that impaired urinary concentrating ability is present in at least half of individuals on chronic lithium therapy, a condition called lithium-induced nephrogenic diabetes insipidus. Continued use of lithium can lead to more serious kidney damage in an aggravated form of diabetes insipidus. Chronic kidney disease caused by lithium has not been proven with various contradicting results presented by a 2018 review. In rare cases, some forms of lithium-caused kidney damage may be progressive and lead to end-stage kidney failure with a reported incidence of 0.2% to 0.7%. Hyperparathyroidism
Lithium-associated hyperparathyroidism is the leading cause of hypercalcemia in lithium-treated patients.
Additionally, increasing dietary sodium intake may also reduce lithium levels by prompting the kidneys to excrete more lithium.Lithium is known to be a potential precipitant of serotonin syndrome in people concurrently on serotonergic medications such as antidepressants, buspirone and certain opioids such as pethidine (meperidine), tramadol, oxycodone, fentanyl and others. Lithium co-treatment is also a risk factor for neuroleptic malignant syndrome in people on antipsychotics and other antidopaminergic medications.High doses of haloperidol, fluphenazine, or flupenthixol may be hazardous when used with lithium; irreversible toxic encephalopathy has been reported. Indeed, these and other antipsychotics have been associated with increased risk of lithium neurotoxicity, even with low therapeutic lithium doses. Overdose
Lithium toxicity, which is also called lithium overdose and lithium poisoning, is the condition of having too much lithium in the blood. This condition also happens in persons that are taking lithium in which the lithium levels are affected by drug interactions in the body. In acute toxicity, people have primarily gastrointestinal symptoms such as vomiting and diarrhea, which may result in volume depletion. During acute toxicity, lithium distributes later into the central nervous system resulting in mild neurological symptoms, such as dizziness.In chronic toxicity, people have primarily neurological symptoms which include nystagmus, tremor, hyperreflexia, ataxia, and change in mental status. During chronic toxicity, the gastrointestinal symptoms seen in acute toxicity are less prominent. The symptoms are often vague and nonspecific.If the lithium toxicity is mild or moderate, lithium dosage is reduced or stopped entirely.