Dermal patches

Organophosphate Ester Hydraulic Fluids. No studies regarding dermal effects in humans after inhalation or oral exposure were located. Erythema was observed in humans repeatedly exposed to dermal patches of Skydrol 500B-4 for an intermediate duration (Monsanto 1980). Skin scabbing was seen after oral exposure to Sanitizer 154 at 300 mg/kg (IRDC 1981). 

When the first-pass effect of a drug going through the liver must be avoided, a parenteral route of administration is usually chosen, although a sublingual route or dermal patch will also avoid the first-pass effect. 

The standard temperature for the dissolution medium is 37 0.5°C for oral dosage forms. Slightly increased temperatures such as 38 0.5°C have been recommended for dosages forms such as suppositories. Lower temperatures such as 32 0.5°C are utilized for topical dosage forms such as trans-dermal patches and topical ointments. 

Nicotine is available for nicotine addicted subjects as gums, dermal patches, lozenges and nasal sprays to help people quit smoking. All these formulations appear to be equally efficacious, approximately doubling the quit rate compared with placebo. However the abstinence rate at one year is often still not higher than 5%. Administration as a... 

Treatment of shingles-related skin pain Topical (Dermal patch) Apply to intact skin over most painful area (up to 3 applications once for up to 12 hr in a 24-hr period). 

Nicotine in tobacco has always been used for medicinal purposes. Nicotine solutions made from soaking tobacco leaves in water have been used as pesticides for several hundred years. In modern times, numerous pharmaceutical companies have explored nicotines use for treating diseases. Nicotines most prevalent medicinal use is for smoking cessation in the form of alternate delivery systems such as gums and dermal patches. Nicotine is used medically for numerous conditions and its use is being explored in additional areas including pain relievers, attention deficit disorder medications and medications associated with Alzheimer s disease, Parkinson disease, colitis, herpes, and tuberculosis. Because of nicotines potential therapeutic use, several large tobacco companies have developed pharmaceutical divisions. 

Testosterone is available as oral testosterone undecano-ate, buccal testosterone, intramuscular testosterone esters, testosterone implants, and testosterone transdermal patches and gel. Proponents of transdermal testosterone products, such as gels and scrotal or non-scrotal dermal patches, claim that they have a good safety profile (101). Transdermal testosterone replacement certainly improves bone mass and lean body mass, reduces fat mass, and improves mood and sexual function. There are said to be no harmful effects on the prostate and lipids. Acne, polycythemia, and gynecomastia are stated to be less common with this form of therapy than with the intramuscular esters. To date these claims must be regarded with some reservations it is not at all clear that in equieffective doses the local or topical forms of administration dissociate wanted and unwanted effects. 

An interaction between nicotinic acid and nicotine trans-dermal patches has also been observed, causing flushing and dizziness (47). 

Solids. Include tablets, capsules, powders, granules, lozenges, pastilles, suppositories, pessaries, pills, dressings, and dermal patches. May also include such devices as actuators. 

Local topical. Applied to the skin—include creams, lotions, ointments, liniments, solutions, pastes, gels, dressings, dermal patches, and aerosols. 

Pyrrolidones show activity with numerous molecules including hydrophilic (e.g., mannitol, 5-fluorouracil, and sulfaguanidine) and lipophilic (betamethasone-17-benzoate, hydrocortisone, and progesterone) permeants. As with many studies, higher flux enhancements have been reported for the hydrophilic molecules. Recently, NMP was employed with limited success as an absorption promoter for captopril when formulated into a matrix-type trans-dermal patch [20]. 

Paranjape M, Garra J, Brida S, Schneider T, White R, Currie J. A PDMS dermal patch for non-intrusive transdermal glucose sensing. Sensors and Actuators A 2003, 104, 195-204. 

Direct Contact This type of drag is absorbed directly through the skin of the user. Many direct contact drags are used with a dermal patch, better known as a "slap patch."... 

The patient should be checked for skin sensitivity before using the trans-dermal patch. Any skin reaction may worsen pruritus already suffered by the patient. 

Table 7.2 Interworker, intertask and intra- and interlocation variability in dermal exposure to captan assessed through hand-rinsing and using dermal patches, in a large population of fruit growers (from De Cock et al., 1998a,b)...

Prokann is a trans dermal patch containing liistamine and this compound... 

Poly(methylvinyl ether/maleic anhydride) copolymers and derivatives are used in denture adhesive bases, controlled-release coatings, enteric coatings, ostomy adhesives, trans-dermal patches, toothpastes, mouthwashes, and trans-dermal gels. Gantrez AN-119 has been used to manufacture... 

Table 8.11 Pressure-sensitive adhesives in trans-dermal patches ...

Briefly, the standard Buehler test uses three 6 h dermal patches, one per week, to the same shaved site. After a 2 week rest period, the test animals and half of the control animals receive another 6h patch at another site. Then, the test animals are tested again 7-15 days later. Reactions are graded according to a five-point scale. If the results are equivocal, the animals may be rechallenged 1 week later. 

Primary Approval Center CDER (drugs) and Consulting Center CDRH (devices) prefilled syringe and dermal patch. 

The above examples have only scratch the surface of the expanding role of the pack. What about dermal patches, implants, insulin pens, pump systems, suppository and pessary delivery systems, nebulisation, puffer packs, Ocuserts , a review of unit dose applications, etc. Systems are now so numerous that doing a paper search and review would take several weeks. However, they do indicate the new roles which are being undertaken by the pack. Each new system challenges new sets of tests in order to evaluate performance and efficiency. 

Dermal patches are another new trend that challenges ingenuity in terms of the material used for the patch and the packaging. In fact it is interesting to note that the theory adopted by the dermal patch, i.e. a drug is incorporated in a polymer matrix from which it diffuses out at a steady rate to penetrate (permeate) the skin, is the converse of that which is normally required for a plastic pack, where no exchange between product and pack is desired. 

Most drugs are not easily absorbed through the skin but some are formulated into dermal patches for systemic absorption and others may penetrate damaged skin. For example, dermal patches can be used to administer nicotine replacement therapy. 

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