Drug of choice for prophylaxis of Mania is
**Core Concept**
Lithium is a mood stabilizer commonly used in the treatment and prophylaxis of bipolar disorder, particularly for the management of acute mania. Its prophylactic effect is believed to be related to its ability to modulate neurotransmitter release and neuronal excitability.
**Why the Correct Answer is Right**
Lithium works by inhibiting the reuptake of neurotransmitters such as serotonin and norepinephrine, thereby increasing their availability in the synaptic cleft. It also has a stabilizing effect on neuronal membranes, which may contribute to its mood-stabilizing properties. The exact mechanism of lithium's prophylactic effect is not fully understood, but it is thought to involve the inhibition of glycogen synthase kinase-3 (GSK-3), an enzyme involved in the signaling pathways of various neurotransmitters.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because lithium is not typically used as a first-line treatment for unipolar depression.
**Option B:** This option is incorrect because antipsychotics, such as haloperidol, are not typically used for prophylaxis of mania; they are more commonly used for acute treatment or as adjunct therapy.
**Option C:** This option is incorrect because carbamazepine is an anticonvulsant mood stabilizer that is often used in the treatment of bipolar disorder, but it is not considered a first-line agent for prophylaxis of mania.
**Clinical Pearl / High-Yield Fact**
It's essential to note that lithium levels should be monitored regularly in patients receiving this medication, as toxicity can occur at high levels. A common mnemonic for the symptoms of lithium toxicity is "Water, Weight, Weakness, Wrist, and Waxy flexibility."
**Correct Answer:** C. Carbamazepine