1. A capsule or a compressed tablet pharmaceutical dosage form comprising a therapeutically effective amount of efavirenz and greater than about 10% by weight of a disintegrant relative to the total dry weight of the pharmaceutical dosage form. 2. A capsule or compressed tablet according to claim 1, wherein the disintegrant is selected from modified starches, croscarmallose sodium, carboxymethylcellulose calcium and crospovidone. 3. A capsule or compressed tablet according to claim 2, wherein the disintegrant is selected from one or more modified starches. 4. A capsule or compressed tablet according to claim 3, wherein the modified starch is sodium starch glycolate. 5. A capsule or compressed tablet according to any preceding claim which is prepared using a wet granulation step containing efavirenz and one or more modified starches, wherein the modified starch is present in the wet granulation step in an amount of from about 10% to about 75% by weight relative to the total dry weight of the components of the wet granulation step. 6. A capsule or compressed tablet according to any preceding claim, wherein the modified starch is present in the wet granulation step of the manufacturing process in an amount of from about 20% to about 55% by weight relative to total dry weight of the components of the wet granulation step. 7. A capsule according to any preceding claim, wherein the efavirenz is present in the pharmaceutical dosage form in an amount of from about 5 to about 1000 mg. 8. A capsule according to any preceding claim, wherein the efavirenz is present in the pharmaceutical dosage form in an amount of from about 5 to about 500 mg. 9. A capsule according to any preceding claim, wherein the efavirenz is present in the pharmaceutical dosage form in an amount of from 500 to about 1000 mg. 10. A capsule according to any preceding claim, wherein the efavirenz is present in the pharmaceutical dosage form in an amount of from about 25 to about 350 mg. 11. A capsule according to any preceding claim, wherein the efavirenz is present in the pharmaceutical dosage form in an amount of from about 50 to about 200 mg. 12. A compressed tablet or capsule according to claim 5-11, wherein the wet granulation step is carried out in the presence of sodium lauryl sulfate. 13. A compressed tablet or capsule according to claim 12, wherein the sodium lauryl sulfate is present in an amount of about 0.1% to about 5% by weight relative to total dry weight of the components of the wet granulation step. 14. A compressed tablet according to claim 1, wherein the efavirenz is present in the pharmaceutical dosage form in an amount of from about 5 to about 800 mg. 15. A pharmaceutical dosage form comprising: (a) a therapeutically effective amount of efavirenz; (b) a surfactant; (c) a disintegrant; (d) a binder; (e) a diluent; (f) a lubricant; (g) a glidant; and (h) optionally additional pharmaceutically acceptable excipients; wherein the disintegrant is selected from modified starches, croscarmallose sodium, carboxymethylcellulose calcium and crospovidone and such disintegrant is present in an amount greater than about 10% by weight of the total dry weight of the capsule contents or the compressed tablet. 16. A method for producing a capsule or a compressed tablet pharmaceutical dosage form comprising a therapeutically effective amount of efavirenz and greater than about 10% by weight of sodium starch glycolate relative to the total dry weight of the pharmaceutical dosage form comprising: (a) wet granulating efavirenz and sodium starch glycolate in the presence of an aqueous solution of sodium lauryl sulfate; (b) drying the product of step (a); (c) milling the product of step (b); (d) dry blending the product of step (c) with sodium starch glycolate and additional pharmaceutically acceptable excipients; and (e) encapsulating or compressing into tablets the product of step (d). 17. A method according to claim 16, wherein: (i) the sodium starch glycolate of step (a) is present in an amount of from about 20% to about 75% by weight relative to the dry weight of all of the components of the wet granulation step; and (ii) the sodium starch glycolate of step (d) is present in an amount of from about 1% to about 10% by weight relative to the total dry weight of all of the components of the dry blending step. 18. A method according to claim 16, wherein: (i) the sodium starch glycolate of step (a) is present in an amount of from about 20% to about 55% by weight relative to the total dry weight of all of the components of the wet granulation step; and (ii) the sodium starch glycolate of step (d) is present in an amount of from about 2% to about 4% by dry weight relative to the total weight of all of the components of the dry blending step.