Drug Dosage Forms. Development of Drug.

Original drug (Brand name drug) – a drug on the market that contains medication not known before. It is protected several years by patent, since a company spent money on research, marketing and promotion. Generic drug – is a drug without patent protection. Needs to be bioequivalent to the brand name drug with respect to pharmacokinetic and pharmacodynamic properties.

Ways of administration Way of administration is the way through which drug reaches organism. Way of adinistration depends on drug form, physical and chemical properties of the drug and psysical and mental state of the patient. Ways of administration are divided to local (topic) and systemic. Systemic administration can be enteral or parenteral. local Administration systemic enteral parenteral

Drug dosage forms can be divided according to consistency to liquid, solid, semisolid and aerosols. Drug dosage forms can also be set for internal or external use.

Solid dosage forms tablets (bucal, sublingual, chewable, effervescent, film- coated, controlled-release = prolonged-release (PR) or sustained-release (SR)) capsules (hard gelatin = dry-filled, soft elastic = the contents may be liquid, paste,or powder, enteric-coated) pills (small round dosage forms prepared by pharmacist, now rarely used) troches (lozenges or pastilles; they are placed in the mouth where they slowly dissolve) powders granules (particularly suitable for the preparation of solutions or mixtures of drugs, that are unstable in the presence of water)

Semisolid dosage forms Ointment (oleaginous bases, most often contain vaselinum or parrafinum liquidum) Cream (emulsion bases, contain a water phase) Paste (forms containing large amounts of solids) Gels (high degree of clarity, ease of application and ease of removal and use; active ingredients are incorporated into water-soluble bases) Suppositories (rectal, vaginal) Plasters (antianginal, analgesic, steroidal drugs)

Liquid dosage forms Prepared by dissolving the active ingredients in an aqueous or nonaqueous solvent: Solutions (homogeneous mixtures that are prepared by dissolving a solid, liquid, or gas in another liquid) Emulsions (two-phase systems in which one liquid is dispersed throughout another liquid in the form of small droplets) Suspensions (two-phase systems consisting of finely divided solids dispersed in liquids) Foams (dispersion of gas in a liquid or solid) Ways of application: Syrups Drops (eye drops can´t be opened more than one month) Enema Injections (i.v., i.m., s.c.) Infusions

Aerosols = Gaseous dosage forms These drugs are designed to carry the drug into the respiratory tract, on the skin and mucous membrane Inhaler (asthma, other respiratory diseases; everyday use) Nebulizer (device to administer medication in form of a liquid mist to airways; used more in hospital)

Drug development synthesis of novel chemical compounds preclinical testing (cell cultures, isolated cells, isolated organs  animals) clinical trials phase I (healthy people) clinical trials phase II (selected patients) clinical trials phase III (large group of patients, the drug is compared to conventional treatments, e.g. “double- blind“ study) registration of the drug (a national regulatory body) clinical trials phase IV (surveillance after licence) 