Lithium drug formulations

Divalproex sodium is comprised of sodium valproate and valproic acid. The delayed-release and extended-release formulations are converted in the small intestine into valproic add, which is the systemically absorbed form. It was developed as an antiepileptic drug, but also has efficacy for mood stabilization and migraine headaches. It is FDA-approved for the treatment of the manic phase of bipolar disorder. It is generally equal in efficacy to lithium and some other drugs for bipolar mania. It has particular utility in bipolar disorder patients with rapid cycling, mixed mood features, and substance abuse comorbidity. Although not FDA-approved for relapse prevention, studies support this use, and it is widely prescribed for maintenance therapy. Divalproex can be used as monotherapy or in combination with lithium or an antipsychotic drug.31... 

Vollmer et al. [4] compared the Hg(II) acetate method described in the Code of Federal Regulations for the determination of penicillamine in bulk drug and formulations with (i) a nonaqueous lithium methoxide titration, (ii) a nonaqueous HCLO4 titration, and (iii) a colorimetric method with hydroxylamine. Method (ii) was unsatisfactory for bulk determinations. Method (i) was less precise than the Hg(II) acetate method, but gave satisfactory results for bulk drug and capsule samples. Method (iii) was the only method that gave satisfactory results in the presence of EDTA. 

Valproate Versus Lithium. The previously discussed Bowden et al. (135) study found the DVPX formulation to be comparable with lithium, which was used as a positive comparator in this placebo-controlled study. Freeman et al. (99) conducted a 3-week, double-blind, parallel-group comparison of VPA and lithium for acute mania. Both drugs demonstrated clinically significant efficacy (i.e., 9 of 14 responded to DVPX and 12 of 13 to lithium), and there was no difference in the need for rescue medications (i.e., lorazepam or chloral hydrate) between the two treatment groups. Response to VPA was associated with high pretreatment depression scores. 

Acetylsalicylic acid is usually given by oral administration (0.5-8 g/day) for pain and inflammation and for antiplatelet therapy (75-100 mg/day). It is also available in rectal and topical formulations and as a soluble lysine derivative for intravenous or intramuscular application. Acetylsalicylic acid is often used in multi-drug preparations. The main side-effects are gastrointestinal disorders. Use in children is limited due to the risk of Reye s syndrome (Waldmann et al., 1982). The lithium, magnesium, calcium, and aluminium salts of acetylsalicylic acid are used in some special preparations. 

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