Capsule size

A wide variety of capsules loaded with water-immiscible or water-iasoluble materials have been prepared by complex coacervation. Capsule size typically ranges from 20—1000 p.m, but capsules outside this range can be prepared. Core contents usually are 80—95 wt %. Complex coacervation processes are adversely affected by active agents that have finite water solubiUty, are surface-active, or are unstable at pH values of 4.0—5.0. The shell of dry complex coacervate capsules is sensitive to variations ia atmospheric moisture content and becomes plasticized at elevated humidities. 

The dose of the drug and its solubility are important considerations in the design of the formulation. The amount and type of active ingredient influences capsule size and the nature and amount of excipients to be used in the formulation. Larger-dose drugs that must be granulated to produce tablets may be more easily direct-filled into hard shell capsules with proper choice of excipients. 

J. G., The effect of capsule size and density on transit through the proximal colon, J. Pharm. Pharmacol. 

Fig. 2a-c. Morphology of an empty capsule. Capsules were produced fromo.6% HV alginate/o.6% cellulose sulfate/1.2% polymethylene-co-guanidine/r% calcium chloride. The reaction time was 30 s. The capsule size is approximately r.6o mm while the membrane thickness is 0.033 mm a the wall complex is clearly evident b progression in the membrane thickness 0.073 mm with reaction time r8o s c progression in the membrane thickness o.ro6 mm with reaction time 300 s... 

As an approximate method for getting an idea about the size of capsule needed, a simple rule of six is very useful. Although not very accurate, the rule of six serves as an initial guide for the capsule size selection. When the bulk density of the powdered material is 0.6 g/cc, this rule helps in obtaining the capsule size which is fairly accurate. However, since the bulk density of pharmaceutical powders is different, it is always a good idea to verify the capsule size by actually filling the material. This rule will certainly narrow down the choice of capsule size selection for initial trials. The rule of six is given below ... 

The above table shows that with the exception of capsule size 0 and 5, the amount of powder in grains that can be filled in the capsules can be obtained by subtracting capsule size from the number six. As an example, five grains or 65 x 5 = 325 mg of powdered drug can be filled in capsule size 1. In capsule size 4, 2 gr or approximately 130 mg of the powder can be filled. Capsule size 5 is an exception because it can be filled with one-half to a grain instead of just 1 gr. Similarly, capsule size 0 can be filled with 6-7 gr instead of just the 6 gr. 

Determine the capsule size by using the rule of six. If the amount of powder is less than the required amount to fill the capsules whose size has been determined, add suitable amount of diluent, preferably lactose, to make up the volume. As a confirmation of the size, fill one or two capsules and determine the appropriateness. If the capsule size is correct punch out the remaining capsules after forming a cake on a powder paper or an ointment tile. 

Step 3 Determine the capsule size by using the rule of six. Capsule size 3 can hold 3 grains or 195 mg. Weigh 200 mg of the tablet mixture (which is obtained as 2000 mg of total powder/10 capsules) and try to fill in capsule size 3. If the capsule is not filled or it is too full, go for the next capsule size, i.e., 2 which holds approximately 4 grains or 260 mg of powder. Verify the appropriateness by filling one or two capsules of size 2. If appropriate, select this size. For 10 capsules, the total powder should be 2600 mg. Therefore add 600 mg of lactose in the tablet mixture of 2000 mg by geometric dilution. Transfer the 2600 mg of powder on a clean paper or an ointment tile, compress as a cake, and fill all the capsules by a sliding motion. 

Step 3 The total powder mixture weighs 5.54 + 2.81 g = 8.35 g. Therefore, the weight of each capsule will be 8.35 g/15 = 0.557 g. Determine the size of the capsule that can hold 0.557 g or 557 mg of the powder. It is known from the rule of six that size 0 can hold up to 7 gr, i.e., 7 x 65 = 455 mg. Obviously, the next capsule size 00 appears to be the right choice. Therefore, fill one or two capsules with 557 mg of the medication powder and determine the appropriateness. If appropriate, transfer all the powder to a clean paper or an ointment tile, form a cake by compressing the powder,... 

The following ten prescriptions are for capsules that are to be prepared either from bulk chemicals or tablets, the information about which is provided following each prescription. For all the prescriptions, check if the subscription is correct and provide all the steps to be followed to fill the prescription. Make sure that all the calculations involved, the capsule size selected, and the label for final container are shown. 

Crush 3 methyldopa tablets and weigh out 2.4 g. Crush 2 tablets of hydralazine and weigh out 0.4 g. Add 0.45 g of lactose, and mix geometrically. Fill 10 capsules appropriately. Capsule size 1 is needed. 

X = 2400 mg of calcium carbonate powder Capsule size 0 is needed. 

After consulting the physician, phenobarbital dose is reduced to 0.025 g. 1800 mg powder of simethicone from 12 tablets, 300 mg of phenobarbital powder, 1200 mg of magnesium carbonate powder from two tablets and 600 mg of lactose are needed for the 12 capsules. Size of the capsules is 1. 

Weigh out 4 HCTZ tabs and 8 triamterene tabs. Crush and add 60 mg of lactose per capsule in the crushed mixture. Punch 10 capsules containing 260 mg of powder in capsule size 2. 

Weight of each capsule = 3300 mg/15 = 220 mg. Therefore, add 40 mg/ capsule of lactose and fill 15 capsules of 260 mg each in capsule size 2. 

Crush 5 methyldopa tablets and weigh out 2880 mg of the powder. Similarly crush two hydralazine tablets and weigh out 400 mg of the powder. Add the two powders to obtain 3280 mg of the total powder. Use capsule size 1 and fill 328 mg in each of the ten capsules. If the powder doesn t fill properly, add additional lactose and fill in capsule size 0. 

FIGURE 3.3 Jar with capsules, each capsule containing a single pol5mer chain where the capsule size is the same and independent of the chain size, illustrating the number-average dependence on molecular weight. 

FIGURE 3.5 Jar with capsules, each containing a single polymer chain where the capsule size is directly related to the size of the polymer chain within the capsule. 

The product used was a hard gelatin capsule, size 0 (Posilok, Elanco), containing coated verapamil hydrochloride pellets (100 mg of verapamil hydrochloride) and coated barium sulphate pellets. 

A tablet or capsule size close to the ideal dose of 350 mg would then be prescribed at 12-hourly intervals. If an 8-hour dosing interval was used, the ideal dose would be 233 mg and if the drug was given once a day, the dose would be 700 mg. In practice, F could be omitted from the calculation since it is so close to 1. 

Capsule shell sizes are generally standardized with Lnite volumes [12,13] available for dispensing the API or powder blend. The capsule size selection would depend on the dose and the bulk density of the NCE. Historically, if the doses were within a reasonable range, it was feasible to dispense API directly into the capsule body utilizing manual, semiautomatic, or automatic high-speed encapsulators available for manufacturing. 

Capsugel capsule sizes and capacities. (2006) http //www.capsugel.com/products/vcaps chart.php... 

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