The drugs cause desired short-term disruptions in the brain, but they also cause undesirable long-term changes to the brain and other vital organs in the body, leading to drug addiction. Common drug addictions include: 1  Marijuana. 2  Heroin. 3  Cocaine/crack. 4  Synthetic drugs such as bath salts and spice.
1 Penicillin G, common vet prescriptions known as CrystacillinÂ® or Flo-CillinÂ®, is an antibiotic used to treat and prevent bacterial infections in dogs and cats. 2  This is a natural penicillin and is cultured from the bacteria Penicillium chrysogenum.
Precautions and Side Effects. 1  While generally safe and effective when prescribed by a veterinarian, penicillin G can cause side effects in some animals. 2  Penicillin G should not be used in animals with known hypersensitivity or allergy to the drug. 3  Penicillin G may interact with other medications.