Caffeine, molecular model. Atoms are represented as spheres and are colour-coded: carbon (black), hydrogen (silver), nitrogen (blue) and oxygen (red).

Melatonin hormone, molecular model. Atoms are represented as spheres and are colour-coded: carbon (black), hydrogen (silver), nitrogen (blue) and oxygen (red).

Cyclobenzaprine muscle relaxant, molecular model. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white) and nitrogen (blue).

Alendronate, molecular model. This osteoporosis drug is marketed as Fosamax. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white), oxygen (red), nitrogen (blue) and phosphorus (orange).

Isosorbide mononitrate, molecular model. This drug is used to treat angina. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white), oxygen (red) and nitrogen (blue).

Loratadine, molecular model. This antihistamine drug is marketed as Claritin. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white), nitrogen (blue), oxygen (red) and chlorine (green).

Brucine, molecular model. This bitter alkaloid is found in several plant species. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white), oxygen (red) and nitrogen (blue).

Tramadol, molecular model. This is a synthetic opioid analgesic (painkiller) drug. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white), nitrogen (blue) and oxygen (red).

Paracetamol molecule. Atoms are represented as spheres and are colour-coded: carbon (black), hydrogen (white), nitrogen (blue) and oxygen (red).

"Neostigmine drug molecule. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

Menthol molecule, computer model. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white) and oxygen (red).

Kekulene hydrocarbon molecule, molecular model. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (blue).

"Paromomycin aminoglycoside antibiotic drug molecule. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

"Primaquine malaria drug molecule. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

"Tropicamide mydriatic eye drug molecule. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

"Paromomycin aminoglycoside antibiotic drug molecule. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

"Tetracaine local anesthetic drug molecule. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

"Indacaterol COPD drug molecule. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

"Primaquine malaria drug molecule. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

"Kanamycin antibiotic drug molecule (aminoglycoside). Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

"Primaquine malaria drug molecule. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

"Peramivir influenza drug molecule (neuraminidase inhibitor). Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

"Lumefantrine (benflumetol) antimalarial drug molecule. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue), chlorine (green). "

"Vincrinstine cancer drug molecule (vinca alkaloid class). Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (grey), oxygen (red), nitrogen (blue). "

Heroin, molecular model. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white), nitrogen (blue) and oxygen (red).